21399722752 has 18 divisors (see below), whose sum is σ = 42715853348. Its totient is φ = 10699861248.

The previous prime is 21399722741. The next prime is 21399722761. The reversal of 21399722752 is 25722799312.

It is a junction number, because it is equal to n+sod(n) for n = 21399722696 and 21399722705.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41796078 + ... + 41796589.

Almost surely, 2^21399722752 is an apocalyptic number.

It is an amenable number.

21399722752 is a deficient number, since it is larger than the sum of its proper divisors (21316130596).

21399722752 is an frugal number, since it uses more digits than its factorization.

21399722752 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83592683 (or 83592669 counting only the distinct ones).

The product of its digits is 952560, while the sum is 49.

The spelling of 21399722752 in words is "twenty-one billion, three hundred ninety-nine million, seven hundred twenty-two thousand, seven hundred fifty-two".