21308811874 has 32 divisors (see below), whose sum is σ = 38709982080. Its totient is φ = 8588083968.

The previous prime is 21308811851. The next prime is 21308811889. The reversal of 21308811874 is 47811880312.

It is a self number, because there is not a number n which added to its sum of digits gives 21308811874.

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 in 15 ways as a sum of consecutive naturals, for example, 258217 + ... + 330595.

It is an arithmetic number, because the mean of its divisors is an integer number (1209686940).

Almost surely, 2^21308811874 is an apocalyptic number.

21308811874 is a deficient number, since it is larger than the sum of its proper divisors (17401170206).

21308811874 is a wasteful number, since it uses less digits than its factorization.

21308811874 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73642.

The product of its (nonzero) digits is 86016, while the sum is 43.

The spelling of 21308811874 in words is "twenty-one billion, three hundred eight million, eight hundred eleven thousand, eight hundred seventy-four".