21551160 has 32 divisors (see below), whose sum is σ = 64653840. Its totient is φ = 5746944.

The previous prime is 21551143. The next prime is 21551171. The reversal of 21551160 is 6115512.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 89677 + ... + 89916.

Almost surely, 2^21551160 is an apocalyptic number.

21551160 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21551160 is an abundant number, since it is smaller than the sum of its proper divisors (43102680).

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

21551160 is a wasteful number, since it uses less digits than its factorization.

21551160 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 179607 (or 179603 counting only the distinct ones).

The product of its (nonzero) digits is 300, while the sum is 21.

The square root of 21551160 is about 4642.3226945140. The cubic root of 21551160 is about 278.2852686514.

Adding to 21551160 its reverse (6115512), we get a palindrome (27666672).

The spelling of 21551160 in words is "twenty-one million, five hundred fifty-one thousand, one hundred sixty".