20856474272 has 24 divisors (see below), whose sum is σ = 42477088500. Its totient is φ = 10068642304.

The previous prime is 20856474253. The next prime is 20856474281. The reversal of 20856474272 is 27247465802.

It can be written as a sum of positive squares in 2 ways, for example, as 18899650576 + 1956823696 = 137476^2 + 44236^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11236397 + ... + 11238252.

Almost surely, 2^20856474272 is an apocalyptic number.

It is an amenable number.

20856474272 is an abundant number, since it is smaller than the sum of its proper divisors (21620614228).

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

20856474272 is a wasteful number, since it uses less digits than its factorization.

20856474272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22474688 (or 22474680 counting only the distinct ones).

The product of its (nonzero) digits is 1505280, while the sum is 47.

The spelling of 20856474272 in words is "twenty billion, eight hundred fifty-six million, four hundred seventy-four thousand, two hundred seventy-two".