21337497539 has 4 divisors (see below), whose sum is σ = 21833718456. Its totient is φ = 20841276624.

The previous prime is 21337497499. The next prime is 21337497569. The reversal of 21337497539 is 93579473312.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21337497539 - 2²⁰ = 21336448963 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21337497569) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 248110394 + ... + 248110479.

It is an arithmetic number, because the mean of its divisors is an integer number (5458429614).

Almost surely, 2^21337497539 is an apocalyptic number.

21337497539 is a deficient number, since it is larger than the sum of its proper divisors (496220917).

21337497539 is an equidigital number, since it uses as much as digits as its factorization.

21337497539 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 496220916.

The product of its digits is 4286520, while the sum is 53.

The spelling of 21337497539 in words is "twenty-one billion, three hundred thirty-seven million, four hundred ninety-seven thousand, five hundred thirty-nine".