21469391874 has 32 divisors (see below), whose sum is σ = 54525440640. Its totient is φ = 6134111856.

The previous prime is 21469391857. The next prime is 21469391891. The reversal of 21469391874 is 47819396412.

21469391874 is a `hidden beast` number, since 21 + 469 + 3 + 91 + 8 + 74 = 666.

It is an interprime number because it is at equal distance from previous prime (21469391857) and next prime (21469391891).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21469391874.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 28398289 + ... + 28399044.

It is an arithmetic number, because the mean of its divisors is an integer number (1703920020).

Almost surely, 2^21469391874 is an apocalyptic number.

21469391874 is an abundant number, since it is smaller than the sum of its proper divisors (33056048766).

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

21469391874 is a wasteful number, since it uses less digits than its factorization.

21469391874 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56797351 (or 56797345 counting only the distinct ones).

The product of its digits is 2612736, while the sum is 54.

The spelling of 21469391874 in words is "twenty-one billion, four hundred sixty-nine million, three hundred ninety-one thousand, eight hundred seventy-four".