21521830412 has 96 divisors (see below), whose sum is σ = 40191427584. Its totient is φ = 10073145600.

The previous prime is 21521830387. The next prime is 21521830439. The reversal of 21521830412 is 21403812512.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 124403558 + ... + 124403730.

It is an arithmetic number, because the mean of its divisors is an integer number (418660704).

Almost surely, 2^21521830412 is an apocalyptic number.

It is an amenable number.

21521830412 is a deficient number, since it is larger than the sum of its proper divisors (18669597172).

21521830412 is a wasteful number, since it uses less digits than its factorization.

21521830412 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 519 (or 517 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 29.

The spelling of 21521830412 in words is "twenty-one billion, five hundred twenty-one million, eight hundred thirty thousand, four hundred twelve".