21315048 has 32 divisors (see below), whose sum is σ = 54194400. Its totient is φ = 6984128.

The previous prime is 21315037. The next prime is 21315053. The reversal of 21315048 is 84051312.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an unprimeable number.

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 in 7 ways as a sum of consecutive naturals, for example, 6111 + ... + 8942.

It is an arithmetic number, because the mean of its divisors is an integer number (1693575).

Almost surely, 2^21315048 is an apocalyptic number.

It is an amenable number.

21315048 is an abundant number, since it is smaller than the sum of its proper divisors (32879352).

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

21315048 is a wasteful number, since it uses less digits than its factorization.

21315048 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15121 (or 15117 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 24.

The square root of 21315048 is about 4616.8222837792. The cubic root of 21315048 is about 277.2652474524.

The spelling of 21315048 in words is "twenty-one million, three hundred fifteen thousand, forty-eight".