21455612 has 12 divisors (see below), whose sum is σ = 37687776. Its totient is φ = 10687680.

The previous prime is 21455593. The next prime is 21455639. The reversal of 21455612 is 21655412.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8813 + ... + 10980.

It is an arithmetic number, because the mean of its divisors is an integer number (3140648).

Almost surely, 2^21455612 is an apocalyptic number.

It is an amenable number.

21455612 is a deficient number, since it is larger than the sum of its proper divisors (16232164).

21455612 is a wasteful number, since it uses less digits than its factorization.

21455612 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20068 (or 20066 counting only the distinct ones).

The product of its digits is 2400, while the sum is 26.

The square root of 21455612 is about 4632.0202935652. The cubic root of 21455612 is about 277.8733961071.

The spelling of 21455612 in words is "twenty-one million, four hundred fifty-five thousand, six hundred twelve".