21948672 has 36 divisors (see below), whose sum is σ = 58417520. Its totient is φ = 7315968.

The previous prime is 21948637. The next prime is 21948673. The reversal of 21948672 is 27684912.

It is a self number, because there is not a number n which added to its sum of digits gives 21948672.

It is not an unprimeable number, because it can be changed into a prime (21948673) 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, 13522 + ... + 15057.

Almost surely, 2^21948672 is an apocalyptic number.

It is an amenable number.

21948672 is an abundant number, since it is smaller than the sum of its proper divisors (36468848).

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

21948672 is an equidigital number, since it uses as much as digits as its factorization.

21948672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28598 (or 28584 counting only the distinct ones).

The product of its digits is 48384, while the sum is 39.

The square root of 21948672 is about 4684.9409814853. The cubic root of 21948672 is about 279.9858496250.

The spelling of 21948672 in words is "twenty-one million, nine hundred forty-eight thousand, six hundred seventy-two".