21315651312 has 40 divisors (see below), whose sum is σ = 56237043456. Its totient is φ = 6954041536.

The previous prime is 21315651299. The next prime is 21315651337.

21315651312 is nontrivially palindromic in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 21315651312.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4721958 + ... + 4726469.

Almost surely, 2^21315651312 is an apocalyptic number.

It is an amenable number.

21315651312 is an abundant number, since it is smaller than the sum of its proper divisors (34921392144).

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

21315651312 is a wasteful number, since it uses less digits than its factorization.

21315651312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9448485 (or 9448479 counting only the distinct ones).

The product of its digits is 5400, while the sum is 30.

The spelling of 21315651312 in words is "twenty-one billion, three hundred fifteen million, six hundred fifty-one thousand, three hundred twelve".