21008451321 has 96 divisors (see below), whose sum is σ = 37306144512. Its totient is φ = 11210158080.

The previous prime is 21008451319. The next prime is 21008451323. The reversal of 21008451321 is 12315480012.

21008451321 is a `hidden beast` number, since 210 + 0 + 84 + 51 + 321 = 666.

It is an interprime number because it is at equal distance from previous prime (21008451319) and next prime (21008451323).

It is not a de Polignac number, because 21008451321 - 2¹ = 21008451319 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21008451323) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 13526881 + ... + 13528433.

It is an arithmetic number, because the mean of its divisors is an integer number (388605672).

Almost surely, 2^21008451321 is an apocalyptic number.

It is an amenable number.

21008451321 is a deficient number, since it is larger than the sum of its proper divisors (16297693191).

21008451321 is a wasteful number, since it uses less digits than its factorization.

21008451321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2063 (or 2060 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The spelling of 21008451321 in words is "twenty-one billion, eight million, four hundred fifty-one thousand, three hundred twenty-one".