21257452 has 12 divisors (see below), whose sum is σ = 37902816. Its totient is φ = 10428080.

The previous prime is 21257419. The next prime is 21257461. The reversal of 21257452 is 25475212.

21257452 is a modest number, since divided by 57452 gives 212 as remainder.

It is a self number, because there is not a number n which added to its sum of digits gives 21257452.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 49924 + ... + 50347.

It is an arithmetic number, because the mean of its divisors is an integer number (3158568).

Almost surely, 2^21257452 is an apocalyptic number.

It is an amenable number.

21257452 is a deficient number, since it is larger than the sum of its proper divisors (16645364).

21257452 is a wasteful number, since it uses less digits than its factorization.

21257452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 100328 (or 100326 counting only the distinct ones).

The product of its digits is 5600, while the sum is 28.

The square root of 21257452 is about 4610.5804406821. The cubic root of 21257452 is about 277.0152867269.

The spelling of 21257452 in words is "twenty-one million, two hundred fifty-seven thousand, four hundred fifty-two".