20659506816 has 256 divisors, whose sum is σ = 63156441600. Its totient is φ = 5930496000.

The previous prime is 20659506811. The next prime is 20659506817. The reversal of 20659506816 is 61860595602.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is not an unprimeable number, because it can be changed into a prime (20659506811) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6353191 + ... + 6356441.

It is an arithmetic number, because the mean of its divisors is an integer number (246704850).

Almost surely, 2^20659506816 is an apocalyptic number.

20659506816 is a gapful number since it is divisible by the number (26) 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 20659506816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31578220800).

20659506816 is an abundant number, since it is smaller than the sum of its proper divisors (42496934784).

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

20659506816 is a wasteful number, since it uses less digits than its factorization.

20659506816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3367 (or 3355 counting only the distinct ones).

The product of its (nonzero) digits is 777600, while the sum is 48.

The spelling of 20659506816 in words is "twenty billion, six hundred fifty-nine million, five hundred six thousand, eight hundred sixteen".