21875384466 has 24 divisors (see below), whose sum is σ = 51042564300. Its totient is φ = 6730887456.

The previous prime is 21875384441. The next prime is 21875384507. The reversal of 21875384466 is 66448357812.

It is a happy number.

21875384466 is a `hidden beast` number, since 2 + 1 + 8 + 7 + 538 + 44 + 66 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 21691103841 + 184280625 = 147279^2 + 13575^2 .

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 11 ways as a sum of consecutive naturals, for example, 46742041 + ... + 46742508.

Almost surely, 2^21875384466 is an apocalyptic number.

21875384466 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

21875384466 is an abundant number, since it is smaller than the sum of its proper divisors (29167179834).

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

21875384466 is a wasteful number, since it uses less digits than its factorization.

21875384466 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93484570 (or 93484567 counting only the distinct ones).

The product of its digits is 7741440, while the sum is 54.

The spelling of 21875384466 in words is "twenty-one billion, eight hundred seventy-five million, three hundred eighty-four thousand, four hundred sixty-six".