20808000000 has 630 divisors, whose sum is σ = 79741030083. Its totient is φ = 5222400000.

The previous prime is 20807999987. The next prime is 20808000007. The reversal of 20808000000 is 80802.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in 11 ways, for example, as 13083699456 + 7724300544 = 114384^2 + 87888^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=102000.

It is a hoax number, since the sum of its digits (18) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is not an unprimeable number, because it can be changed into a prime (20808000007) by changing a digit.

It is a polite number, since it can be written in 62 ways as a sum of consecutive naturals, for example, 1223999992 + ... + 1224000008.

Almost surely, 2^20808000000 is an apocalyptic number.

20808000000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20808000000

20808000000 is an abundant number, since it is smaller than the sum of its proper divisors (58933030083).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20808000000 is an frugal number, since it uses more digits than its factorization.

20808000000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88 (or 27 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Multiplying 20808000000 by its sum of digits (18), we get a square (374544000000 = 612000²).

20808000000 divided by its sum of digits (18) gives a square (1156000000 = 34000²).

Multiplying 20808000000 by its product of nonzero digits (128), we get a square (2663424000000 = 1632000²).

20808000000 divided by its product of nonzero digits (128) gives a square (162562500 = 12750²).

Adding to 20808000000 its reverse (80802), we get a palindrome (20808080802).

The spelling of 20808000000 in words is "twenty billion, eight hundred eight million", and thus it is an aban number.