21064272 has 40 divisors (see below), whose sum is σ = 55579776. Its totient is φ = 6871296.

The previous prime is 21064271. The next prime is 21064273. The reversal of 21064272 is 27246012.

It is an interprime number because it is at equal distance from previous prime (21064271) and next prime (21064273).

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

It is a zygodrome in base 4.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21064271) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2413 + ... + 6924.

Almost surely, 2^21064272 is an apocalyptic number.

It is an amenable number.

21064272 is an abundant number, since it is smaller than the sum of its proper divisors (34515504).

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

21064272 is a wasteful number, since it uses less digits than its factorization.

21064272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9395 (or 9389 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 24.

The square root of 21064272 is about 4589.5829875927. The cubic root of 21064272 is about 276.1735937966.

The spelling of 21064272 in words is "twenty-one million, sixty-four thousand, two hundred seventy-two".