21725375 has 24 divisors (see below), whose sum is σ = 31548816. Its totient is φ = 14893200.

The previous prime is 21725369. The next prime is 21725383. The reversal of 21725375 is 57352712.

It is not a de Polignac number, because 21725375 - 2¹² = 21721279 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 in 23 ways as a sum of consecutive naturals, for example, 4352 + ... + 7898.

It is an arithmetic number, because the mean of its divisors is an integer number (1314534).

Almost surely, 2^21725375 is an apocalyptic number.

21725375 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21725375 is a deficient number, since it is larger than the sum of its proper divisors (9823441).

21725375 is an equidigital number, since it uses as much as digits as its factorization.

21725375 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3576 (or 3559 counting only the distinct ones).

The product of its digits is 14700, while the sum is 32.

The square root of 21725375 is about 4661.0487017408. The cubic root of 21725375 is about 279.0331234253.

The spelling of 21725375 in words is "twenty-one million, seven hundred twenty-five thousand, three hundred seventy-five".