21252508 has 12 divisors (see below), whose sum is σ = 37822680. Its totient is φ = 10446032.

The previous prime is 21252503. The next prime is 21252509. The reversal of 21252508 is 80525212.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21252503) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 44791 + ... + 45262.

It is an arithmetic number, because the mean of its divisors is an integer number (3151890).

Almost surely, 2^21252508 is an apocalyptic number.

It is an amenable number.

21252508 is a deficient number, since it is larger than the sum of its proper divisors (16570172).

21252508 is a wasteful number, since it uses less digits than its factorization.

21252508 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90116 (or 90114 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 25.

The square root of 21252508 is about 4610.0442514145. The cubic root of 21252508 is about 276.9938092427.

The spelling of 21252508 in words is "twenty-one million, two hundred fifty-two thousand, five hundred eight".