21437452 has 24 divisors (see below), whose sum is σ = 38727360. Its totient is φ = 10377600.

The previous prime is 21437443. The next prime is 21437501. The reversal of 21437452 is 25473412.

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 21437452.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18424 + ... + 19552.

It is an arithmetic number, because the mean of its divisors is an integer number (1613640).

Almost surely, 2^21437452 is an apocalyptic number.

It is an amenable number.

21437452 is a deficient number, since it is larger than the sum of its proper divisors (17289908).

21437452 is a wasteful number, since it uses less digits than its factorization.

21437452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1281 (or 1279 counting only the distinct ones).

The product of its digits is 6720, while the sum is 28.

The square root of 21437452 is about 4630.0596108474. The cubic root of 21437452 is about 277.7949767603.

The spelling of 21437452 in words is "twenty-one million, four hundred thirty-seven thousand, four hundred fifty-two".