21152790 has 48 divisors (see below), whose sum is σ = 55587168. Its totient is φ = 5580288.

The previous prime is 21152783. The next prime is 21152797. The reversal of 21152790 is 9725112.

It is an interprime number because it is at equal distance from previous prime (21152783) and next prime (21152797).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21152797) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7519 + ... + 9941.

It is an arithmetic number, because the mean of its divisors is an integer number (1158066).

Almost surely, 2^21152790 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21152790, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27793584).

21152790 is an abundant number, since it is smaller than the sum of its proper divisors (34434378).

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

21152790 is a wasteful number, since it uses less digits than its factorization.

21152790 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2533 (or 2530 counting only the distinct ones).

The product of its (nonzero) digits is 1260, while the sum is 27.

The square root of 21152790 is about 4599.2162375779. The cubic root of 21152790 is about 276.5599062287.

The spelling of 21152790 in words is "twenty-one million, one hundred fifty-two thousand, seven hundred ninety".