21186791324 has 12 divisors (see below), whose sum is σ = 37203429144. Its totient is φ = 10557240144.

The previous prime is 21186791303. The next prime is 21186791333. The reversal of 21186791324 is 42319768112.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9037562 + ... + 9039905.

It is an arithmetic number, because the mean of its divisors is an integer number (3100285762).

Almost surely, 2^21186791324 is an apocalyptic number.

It is an amenable number.

21186791324 is a deficient number, since it is larger than the sum of its proper divisors (16016637820).

21186791324 is a wasteful number, since it uses less digits than its factorization.

21186791324 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18077764 (or 18077762 counting only the distinct ones).

The product of its digits is 145152, while the sum is 44.

The spelling of 21186791324 in words is "twenty-one billion, one hundred eighty-six million, seven hundred ninety-one thousand, three hundred twenty-four".