21612412 has 12 divisors (see below), whose sum is σ = 38744496. Its totient is φ = 10542560.

The previous prime is 21612397. The next prime is 21612413. The reversal of 21612412 is 21421612.

It is a self number, because there is not a number n which added to its sum of digits gives 21612412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21612413) 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, 65728 + ... + 66055.

It is an arithmetic number, because the mean of its divisors is an integer number (3228708).

Almost surely, 2^21612412 is an apocalyptic number.

It is an amenable number.

21612412 is a deficient number, since it is larger than the sum of its proper divisors (17132084).

21612412 is a wasteful number, since it uses less digits than its factorization.

21612412 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131828 (or 131826 counting only the distinct ones).

The product of its digits is 192, while the sum is 19.

The square root of 21612412 is about 4648.9151422671. The cubic root of 21612412 is about 278.5486636918.

The spelling of 21612412 in words is "twenty-one million, six hundred twelve thousand, four hundred twelve".