21659160 has 64 divisors (see below), whose sum is σ = 65376000. Its totient is φ = 5740416.

The previous prime is 21659153. The next prime is 21659161. The reversal of 21659160 is 6195612.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21659161) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23427 + ... + 24333.

It is an arithmetic number, because the mean of its divisors is an integer number (1021500).

Almost surely, 2^21659160 is an apocalyptic number.

21659160 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 21659160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32688000).

21659160 is an abundant number, since it is smaller than the sum of its proper divisors (43716840).

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

21659160 is a wasteful number, since it uses less digits than its factorization.

21659160 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1120 (or 1116 counting only the distinct ones).

The product of its (nonzero) digits is 3240, while the sum is 30.

The square root of 21659160 is about 4653.9402660541. The cubic root of 21659160 is about 278.7493541648.

It can be divided in two parts, 2165 and 9160, that added together give a triangular number (11325 = T₁₅₀).

The spelling of 21659160 in words is "twenty-one million, six hundred fifty-nine thousand, one hundred sixty".