21812152 has 16 divisors (see below), whose sum is σ = 43050600. Its totient is φ = 10332000.

The previous prime is 21812149. The next prime is 21812179. The reversal of 21812152 is 25121812.

It is a super-2 number, since 2×21812152² = 951539949742208, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 71599 + ... + 71902.

Almost surely, 2^21812152 is an apocalyptic number.

It is an amenable number.

21812152 is a deficient number, since it is larger than the sum of its proper divisors (21238448).

21812152 is a wasteful number, since it uses less digits than its factorization.

21812152 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143526 (or 143522 counting only the distinct ones).

The product of its digits is 320, while the sum is 22.

The square root of 21812152 is about 4670.3481668929. The cubic root of 21812152 is about 279.4041410345.

Adding to 21812152 its reverse (25121812), we get a palindrome (46933964).

The spelling of 21812152 in words is "twenty-one million, eight hundred twelve thousand, one hundred fifty-two".