21948816 has 20 divisors (see below), whose sum is σ = 56701232. Its totient is φ = 7316256.

The previous prime is 21948811. The next prime is 21948821. The reversal of 21948816 is 61884912.

It is an interprime number because it is at equal distance from previous prime (21948811) and next prime (21948821).

It is not an unprimeable number, because it can be changed into a prime (21948811) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 228586 + ... + 228681.

Almost surely, 2^21948816 is an apocalyptic number.

It is an amenable number.

21948816 is an abundant number, since it is smaller than the sum of its proper divisors (34752416).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21948816 is a wasteful number, since it uses less digits than its factorization.

21948816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 457278 (or 457272 counting only the distinct ones).

The product of its digits is 27648, while the sum is 39.

The square root of 21948816 is about 4684.9563498500. The cubic root of 21948816 is about 279.9864619305.

It can be divided in two parts, 219488 and 16, that multiplied together give a cube (3511808 = 152³).

The spelling of 21948816 in words is "twenty-one million, nine hundred forty-eight thousand, eight hundred sixteen".