21847818837 has 16 divisors (see below), whose sum is σ = 31435671680. Its totient is φ = 13417192512.

The previous prime is 21847818739. The next prime is 21847818859. The reversal of 21847818837 is 73881874812.

It is not a de Polignac number, because 21847818837 - 2⁷ = 21847818709 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21847813837) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 556162 + ... + 594147.

It is an arithmetic number, because the mean of its divisors is an integer number (1964729480).

Almost surely, 2^21847818837 is an apocalyptic number.

It is an amenable number.

21847818837 is a deficient number, since it is larger than the sum of its proper divisors (9587852843).

21847818837 is a wasteful number, since it uses less digits than its factorization.

21847818837 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1150812.

The product of its digits is 4816896, while the sum is 57.

The spelling of 21847818837 in words is "twenty-one billion, eight hundred forty-seven million, eight hundred eighteen thousand, eight hundred thirty-seven".