21475256 has 32 divisors (see below), whose sum is σ = 44135280. Its totient is φ = 9715200.

The previous prime is 21475253. The next prime is 21475271. The reversal of 21475256 is 65257412.

It is a super-2 number, since 2×21475256² = 922373240531072, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21475253) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23936 + ... + 24816.

Almost surely, 2^21475256 is an apocalyptic number.

It is an amenable number.

21475256 is an abundant number, since it is smaller than the sum of its proper divisors (22660024).

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

21475256 is a wasteful number, since it uses less digits than its factorization.

21475256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1175 (or 1171 counting only the distinct ones).

The product of its digits is 16800, while the sum is 32.

The square root of 21475256 is about 4634.1402654646. The cubic root of 21475256 is about 277.9581739259.

The spelling of 21475256 in words is "twenty-one million, four hundred seventy-five thousand, two hundred fifty-six".