21017268 has 36 divisors (see below), whose sum is σ = 55924960. Its totient is φ = 6636816.

The previous prime is 21017233. The next prime is 21017273. The reversal of 21017268 is 86271012.

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 14680 + ... + 16047.

Almost surely, 2^21017268 is an apocalyptic number.

It is an amenable number.

21017268 is an abundant number, since it is smaller than the sum of its proper divisors (34907692).

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

21017268 is a wasteful number, since it uses less digits than its factorization.

21017268 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30756 (or 30751 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 27.

The square root of 21017268 is about 4584.4594010636. The cubic root of 21017268 is about 275.9680177182.

The spelling of 21017268 in words is "twenty-one million, seventeen thousand, two hundred sixty-eight".