21256536060 has 72 divisors (see below), whose sum is σ = 67281570720. Its totient is φ = 5421955968.

The previous prime is 21256536043. The next prime is 21256536071. The reversal of 21256536060 is 6063565212.

It is a happy number.

21256536060 is a `hidden beast` number, since 2 + 1 + 2 + 565 + 36 + 0 + 60 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2563075 + ... + 2571354.

It is an arithmetic number, because the mean of its divisors is an integer number (934466260).

Almost surely, 2^21256536060 is an apocalyptic number.

21256536060 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21256536060 is an abundant number, since it is smaller than the sum of its proper divisors (46025034660).

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

21256536060 is a wasteful number, since it uses less digits than its factorization.

21256536060 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5134467 (or 5134462 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 36.

The spelling of 21256536060 in words is "twenty-one billion, two hundred fifty-six million, five hundred thirty-six thousand, sixty".