21266248 has 16 divisors (see below), whose sum is σ = 41160960. Its totient is φ = 10290000.

The previous prime is 21266239. The next prime is 21266291. The reversal of 21266248 is 84266212.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42628 + ... + 43123.

It is an arithmetic number, because the mean of its divisors is an integer number (2572560).

Almost surely, 2^21266248 is an apocalyptic number.

It is an amenable number.

21266248 is a deficient number, since it is larger than the sum of its proper divisors (19894712).

21266248 is a wasteful number, since it uses less digits than its factorization.

21266248 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85788 (or 85784 counting only the distinct ones).

The product of its digits is 9216, while the sum is 31.

The square root of 21266248 is about 4611.5342349374. The cubic root of 21266248 is about 277.0534896508.

The spelling of 21266248 in words is "twenty-one million, two hundred sixty-six thousand, two hundred forty-eight".