21198252 has 24 divisors (see below), whose sum is σ = 52372656. Its totient is φ = 6650368.

The previous prime is 21198241. The next prime is 21198253. The reversal of 21198252 is 25289112.

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (21198253) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 51753 + ... + 52160.

It is an arithmetic number, because the mean of its divisors is an integer number (2182194).

Almost surely, 2^21198252 is an apocalyptic number.

It is an amenable number.

21198252 is an abundant number, since it is smaller than the sum of its proper divisors (31174404).

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

21198252 is a wasteful number, since it uses less digits than its factorization.

21198252 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103937 (or 103935 counting only the distinct ones).

The product of its digits is 2880, while the sum is 30.

The square root of 21198252 is about 4604.1559487055. The cubic root of 21198252 is about 276.7578938202.

The spelling of 21198252 in words is "twenty-one million, one hundred ninety-eight thousand, two hundred fifty-two".