21365564457675 has 48 divisors (see below), whose sum is σ = 37485608133600. Its totient is φ = 10700789514240.

The previous prime is 21365564457661. The next prime is 21365564457689. The reversal of 21365564457675 is 57675446556312.

It is an interprime number because it is at equal distance from previous prime (21365564457661) and next prime (21365564457689).

It is not a de Polignac number, because 21365564457675 - 2⁴ = 21365564457659 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 18088222 + ... + 19233171.

It is an arithmetic number, because the mean of its divisors is an integer number (780950169450).

Almost surely, 2^{21365564457675} is an apocalyptic number.

21365564457675 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21365564457675 is a deficient number, since it is larger than the sum of its proper divisors (16120043675925).

21365564457675 is a wasteful number, since it uses less digits than its factorization.

21365564457675 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37321872 (or 37321867 counting only the distinct ones).

The product of its digits is 635040000, while the sum is 66.

The spelling of 21365564457675 in words is "twenty-one trillion, three hundred sixty-five billion, five hundred sixty-four million, four hundred fifty-seven thousand, six hundred seventy-five".