20887357956 has 48 divisors (see below), whose sum is σ = 50244991104. Its totient is φ = 6748482816.

The previous prime is 20887357903. The next prime is 20887357957. The reversal of 20887357956 is 65975378802.

It is a hoax number, since the sum of its digits (60) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 20887357956.

It is not an unprimeable number, because it can be changed into a prime (20887357957) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27336 + ... + 206208.

It is an arithmetic number, because the mean of its divisors is an integer number (1046770648).

Almost surely, 2^20887357956 is an apocalyptic number.

It is an amenable number.

20887357956 is an abundant number, since it is smaller than the sum of its proper divisors (29357633148).

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

20887357956 is a wasteful number, since it uses less digits than its factorization.

20887357956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 179180 (or 179178 counting only the distinct ones).

The product of its (nonzero) digits is 25401600, while the sum is 60.

The spelling of 20887357956 in words is "twenty billion, eight hundred eighty-seven million, three hundred fifty-seven thousand, nine hundred fifty-six".