21215692530 has 80 divisors (see below), whose sum is σ = 57768923520. Its totient is φ = 5585887008.

The previous prime is 21215692523. The next prime is 21215692559. The reversal of 21215692530 is 3529651212.

It is a happy number.

21215692530 is a `hidden beast` number, since 21 + 2 + 15 + 6 + 92 + 530 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 101784 + ... + 229763.

It is an arithmetic number, because the mean of its divisors is an integer number (722111544).

Almost surely, 2^21215692530 is an apocalyptic number.

21215692530 is an abundant number, since it is smaller than the sum of its proper divisors (36553230990).

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

21215692530 is a wasteful number, since it uses less digits than its factorization.

21215692530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 331645 (or 331636 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 36.

The spelling of 21215692530 in words is "twenty-one billion, two hundred fifteen million, six hundred ninety-two thousand, five hundred thirty".