21930360 has 64 divisors (see below), whose sum is σ = 66355200. Its totient is φ = 5798016.

The previous prime is 21930347. The next prime is 21930371. The reversal of 21930360 is 6303912.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21930360.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14521 + ... + 15959.

It is an arithmetic number, because the mean of its divisors is an integer number (1036800).

Almost surely, 2^21930360 is an apocalyptic number.

21930360 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 21930360, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33177600).

21930360 is an abundant number, since it is smaller than the sum of its proper divisors (44424840).

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

21930360 is a wasteful number, since it uses less digits than its factorization.

21930360 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1580 (or 1576 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 24.

The square root of 21930360 is about 4682.9862267575. The cubic root of 21930360 is about 279.9079629477.

The spelling of 21930360 in words is "twenty-one million, nine hundred thirty thousand, three hundred sixty".