21347744136 has 32 divisors (see below), whose sum is σ = 53385229440. Its totient is φ = 7113798848.

The previous prime is 21347744083. The next prime is 21347744137. The reversal of 21347744136 is 63144774312.

It is a super-2 number, since 2×21347744136² (a number of 21 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (42) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (21347744137) by changing a digit.

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 in 7 ways as a sum of consecutive naturals, for example, 48771 + ... + 212306.

It is an arithmetic number, because the mean of its divisors is an integer number (1668288420).

Almost surely, 2^21347744136 is an apocalyptic number.

It is an amenable number.

21347744136 is an abundant number, since it is smaller than the sum of its proper divisors (32037485304).

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

21347744136 is a wasteful number, since it uses less digits than its factorization.

21347744136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 264493 (or 264489 counting only the distinct ones).

The product of its digits is 338688, while the sum is 42.

The spelling of 21347744136 in words is "twenty-one billion, three hundred forty-seven million, seven hundred forty-four thousand, one hundred thirty-six".