21396712 has 16 divisors (see below), whose sum is σ = 40225860. Its totient is φ = 10669824.

The previous prime is 21396709. The next prime is 21396731. The reversal of 21396712 is 21769312.

It can be written as a sum of positive squares in 2 ways, for example, as 21215236 + 181476 = 4606^2 + 426^2 .

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, 193 + ... + 6544.

Almost surely, 2^21396712 is an apocalyptic number.

It is an amenable number.

21396712 is a deficient number, since it is larger than the sum of its proper divisors (18829148).

21396712 is a wasteful number, since it uses less digits than its factorization.

21396712 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7140 (or 7136 counting only the distinct ones).

The product of its digits is 4536, while the sum is 31.

The square root of 21396712 is about 4625.6580072461. The cubic root of 21396712 is about 277.6188901595.

The spelling of 21396712 in words is "twenty-one million, three hundred ninety-six thousand, seven hundred twelve".