21059875 has 16 divisors (see below), whose sum is σ = 26413920. Its totient is φ = 16764000.

The previous prime is 21059867. The next prime is 21059879. The reversal of 21059875 is 57895012.

It is not a de Polignac number, because 21059875 - 2³ = 21059867 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21059879) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 41121 + ... + 41629.

It is an arithmetic number, because the mean of its divisors is an integer number (1650870).

Almost surely, 2^21059875 is an apocalyptic number.

21059875 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21059875 is a deficient number, since it is larger than the sum of its proper divisors (5354045).

21059875 is an equidigital number, since it uses as much as digits as its factorization.

21059875 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 855 (or 845 counting only the distinct ones).

The product of its (nonzero) digits is 25200, while the sum is 37.

The square root of 21059875 is about 4589.1039430372. The cubic root of 21059875 is about 276.1543761090.

The spelling of 21059875 in words is "twenty-one million, fifty-nine thousand, eight hundred seventy-five".