21137297952 has 48 divisors (see below), whose sum is σ = 55496351232. Its totient is φ = 7044376320.

The previous prime is 21137297917. The next prime is 21137297963. The reversal of 21137297952 is 25979273112.

It is a tau number, because it is divible by the number of its divisors (48).

It is a Harshad number since it is a multiple of its sum of digits (48).

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, 543873 + ... + 581439.

It is an arithmetic number, because the mean of its divisors is an integer number (1156173984).

Almost surely, 2^21137297952 is an apocalyptic number.

It is an amenable number.

21137297952 is an abundant number, since it is smaller than the sum of its proper divisors (34359053280).

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

21137297952 is a wasteful number, since it uses less digits than its factorization.

21137297952 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43441 (or 43433 counting only the distinct ones).

The product of its digits is 476280, while the sum is 48.

The spelling of 21137297952 in words is "twenty-one billion, one hundred thirty-seven million, two hundred ninety-seven thousand, nine hundred fifty-two".