20956755648 has 56 divisors (see below), whose sum is σ = 55884746752. Its totient is φ = 6930572544.

The previous prime is 20956755623. The next prime is 20956755649. The reversal of 20956755648 is 84655765902.

It is not an unprimeable number, because it can be changed into a prime (20956755649) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 405340 + ... + 454107.

Almost surely, 2^20956755648 is an apocalyptic number.

It is an amenable number.

20956755648 is an abundant number, since it is smaller than the sum of its proper divisors (34927991104).

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

20956755648 is a wasteful number, since it uses less digits than its factorization.

20956755648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 859589 (or 859579 counting only the distinct ones).

The product of its (nonzero) digits is 18144000, while the sum is 57.

The spelling of 20956755648 in words is "twenty billion, nine hundred fifty-six million, seven hundred fifty-five thousand, six hundred forty-eight".