21967408 has 10 divisors (see below), whose sum is σ = 42561884. Its totient is φ = 10983696.

The previous prime is 21967403. The next prime is 21967409. The reversal of 21967408 is 80476912.

It is not an unprimeable number, because it can be changed into a prime (21967403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 686466 + ... + 686497.

Almost surely, 2^21967408 is an apocalyptic number.

It is an amenable number.

21967408 is a deficient number, since it is larger than the sum of its proper divisors (20594476).

21967408 is a wasteful number, since it uses less digits than its factorization.

21967408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1372971 (or 1372965 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 37.

The square root of 21967408 is about 4686.9401532343. The cubic root of 21967408 is about 280.0654948830.

It can be divided in two parts, 2196 and 7408, that added together give a square (9604 = 98²).

The spelling of 21967408 in words is "twenty-one million, nine hundred sixty-seven thousand, four hundred eight".