21675872 has 12 divisors (see below), whose sum is σ = 42674436. Its totient is φ = 10837920.

The previous prime is 21675869. The next prime is 21675877. The reversal of 21675872 is 27857612.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21675877) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 338654 + ... + 338717.

It is an arithmetic number, because the mean of its divisors is an integer number (3556203).

Almost surely, 2^21675872 is an apocalyptic number.

It is an amenable number.

21675872 is a deficient number, since it is larger than the sum of its proper divisors (20998564).

21675872 is an equidigital number, since it uses as much as digits as its factorization.

21675872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 677381 (or 677373 counting only the distinct ones).

The product of its digits is 47040, while the sum is 38.

The square root of 21675872 is about 4655.7353876697. The cubic root of 21675872 is about 278.8210291755.

The spelling of 21675872 in words is "twenty-one million, six hundred seventy-five thousand, eight hundred seventy-two".