21530203512 has 32 divisors (see below), whose sum is σ = 53980646400. Its totient is φ = 7156049504.

The previous prime is 21530203493. The next prime is 21530203523.

It is a happy number.

21530203512 is nontrivially palindromic in base 10.

It is a Harshad number since it is a multiple of its sum of digits (24).

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, 1284312 + ... + 1300967.

It is an arithmetic number, because the mean of its divisors is an integer number (1686895200).

Almost surely, 2^21530203512 is an apocalyptic number.

It is an amenable number.

21530203512 is an abundant number, since it is smaller than the sum of its proper divisors (32450442888).

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

21530203512 is a wasteful number, since it uses less digits than its factorization.

21530203512 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2585635 (or 2585631 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 24.

The spelling of 21530203512 in words is "twenty-one billion, five hundred thirty million, two hundred three thousand, five hundred twelve".