21817884374 has 24 divisors (see below), whose sum is σ = 38739580320. Its totient is φ = 9154355760.

The previous prime is 21817884373. The next prime is 21817884421. The reversal of 21817884374 is 47348871812.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21817884373) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3464414 + ... + 3470705.

It is an arithmetic number, because the mean of its divisors is an integer number (1614149180).

Almost surely, 2^21817884374 is an apocalyptic number.

21817884374 is a deficient number, since it is larger than the sum of its proper divisors (16921695946).

21817884374 is a wasteful number, since it uses less digits than its factorization.

21817884374 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6935156 (or 6935145 counting only the distinct ones).

The product of its digits is 2408448, while the sum is 53.

The spelling of 21817884374 in words is "twenty-one billion, eight hundred seventeen million, eight hundred eighty-four thousand, three hundred seventy-four".