20859229656 has 96 divisors (see below), whose sum is σ = 59115438720. Its totient is φ = 6636556800.

The previous prime is 20859229639. The next prime is 20859229661. The reversal of 20859229656 is 65692295802.

20859229656 is a `hidden beast` number, since 20 + 8 + 592 + 29 + 6 + 5 + 6 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 98926 + ... + 226946.

It is an arithmetic number, because the mean of its divisors is an integer number (615785820).

Almost surely, 2^20859229656 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20859229656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29557719360).

20859229656 is an abundant number, since it is smaller than the sum of its proper divisors (38256209064).

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

20859229656 is a wasteful number, since it uses less digits than its factorization.

20859229656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128137 (or 128130 counting only the distinct ones).

The product of its (nonzero) digits is 4665600, while the sum is 54.

The spelling of 20859229656 in words is "twenty billion, eight hundred fifty-nine million, two hundred twenty-nine thousand, six hundred fifty-six".