21915360 has 240 divisors, whose sum is σ = 82328400. Its totient is φ = 5474304.

The previous prime is 21915331. The next prime is 21915371. The reversal of 21915360 is 6351912.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 246196 + ... + 246284.

It is an arithmetic number, because the mean of its divisors is an integer number (343035).

Almost surely, 2^21915360 is an apocalyptic number.

21915360 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21915360, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41164200).

21915360 is an abundant number, since it is smaller than the sum of its proper divisors (60413040).

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

21915360 is a wasteful number, since it uses less digits than its factorization.

21915360 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135 (or 118 counting only the distinct ones).

The product of its (nonzero) digits is 1620, while the sum is 27.

The square root of 21915360 is about 4681.3844106204. The cubic root of 21915360 is about 279.8441309347.

The spelling of 21915360 in words is "twenty-one million, nine hundred fifteen thousand, three hundred sixty".