21231645376 has 28 divisors (see below), whose sum is σ = 42366940920. Its totient is φ = 10556510720.

The previous prime is 21231645353. The next prime is 21231645401. The reversal of 21231645376 is 67354613212.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 915205 + ... + 938116.

Almost surely, 2^21231645376 is an apocalyptic number.

It is an amenable number.

21231645376 is a deficient number, since it is larger than the sum of its proper divisors (21135295544).

21231645376 is a wasteful number, since it uses less digits than its factorization.

21231645376 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1853512 (or 1853502 counting only the distinct ones).

The product of its digits is 181440, while the sum is 40.

The spelling of 21231645376 in words is "twenty-one billion, two hundred thirty-one million, six hundred forty-five thousand, three hundred seventy-six".