21249464 has 8 divisors (see below), whose sum is σ = 39842760. Its totient is φ = 10624728.

The previous prime is 21249443. The next prime is 21249523. The reversal of 21249464 is 46494212.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21249464.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1328084 + ... + 1328099.

It is an arithmetic number, because the mean of its divisors is an integer number (4980345).

Almost surely, 2^21249464 is an apocalyptic number.

It is an amenable number.

21249464 is a deficient number, since it is larger than the sum of its proper divisors (18593296).

21249464 is a wasteful number, since it uses less digits than its factorization.

21249464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2656189 (or 2656185 counting only the distinct ones).

The product of its digits is 13824, while the sum is 32.

The square root of 21249464 is about 4609.7140909171. The cubic root of 21249464 is about 276.9805839893.

The spelling of 21249464 in words is "twenty-one million, two hundred forty-nine thousand, four hundred sixty-four".