21915496 has 8 divisors (see below), whose sum is σ = 41091570. Its totient is φ = 10957744.

The previous prime is 21915463. The next prime is 21915497. The reversal of 21915496 is 69451912.

It can be written as a sum of positive squares in only one way, i.e., 11764900 + 10150596 = 3430^2 + 3186^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (21915497) 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 as a sum of consecutive naturals, namely, 1369711 + ... + 1369726.

Almost surely, 2^21915496 is an apocalyptic number.

It is an amenable number.

21915496 is a deficient number, since it is larger than the sum of its proper divisors (19176074).

21915496 is a wasteful number, since it uses less digits than its factorization.

21915496 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2739443 (or 2739439 counting only the distinct ones).

The product of its digits is 19440, while the sum is 37.

The square root of 21915496 is about 4681.3989362155. The cubic root of 21915496 is about 279.8447098091.

The spelling of 21915496 in words is "twenty-one million, nine hundred fifteen thousand, four hundred ninety-six".