20491315200 has 648 divisors, whose sum is σ = 77454476190. Its totient is φ = 5374771200.

The previous prime is 20491315199. The next prime is 20491315219. The reversal of 20491315200 is 251319402.

20491315200 is a `hidden beast` number, since 2 + 0 + 4 + 9 + 131 + 520 + 0 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 9197577216 + 11293737984 = 95904^2 + 106272^2 .

It is a tau number, because it is divible by the number of its divisors (648).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 335923170 + ... + 335923230.

Almost surely, 2^20491315200 is an apocalyptic number.

20491315200 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 20491315200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38727238095).

20491315200 is an abundant number, since it is smaller than the sum of its proper divisors (56963160990).

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

20491315200 is an frugal number, since it uses more digits than its factorization.

20491315200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117 (or 71 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The spelling of 20491315200 in words is "twenty billion, four hundred ninety-one million, three hundred fifteen thousand, two hundred".