21421612 has 12 divisors (see below), whose sum is σ = 37547496. Its totient is φ = 10693760.

The previous prime is 21421597. The next prime is 21421619. The reversal of 21421612 is 21612412.

It is a self number, because there is not a number n which added to its sum of digits gives 21421612.

It is not an unprimeable number, because it can be changed into a prime (21421619) 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 3 ways as a sum of consecutive naturals, for example, 1189 + ... + 6652.

It is an arithmetic number, because the mean of its divisors is an integer number (3128958).

Almost surely, 2^21421612 is an apocalyptic number.

It is an amenable number.

21421612 is a deficient number, since it is larger than the sum of its proper divisors (16125884).

21421612 is a wasteful number, since it uses less digits than its factorization.

21421612 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8528 (or 8526 counting only the distinct ones).

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

The square root of 21421612 is about 4628.3487336198. The cubic root of 21421612 is about 277.7265395745.

The spelling of 21421612 in words is "twenty-one million, four hundred twenty-one thousand, six hundred twelve".