21157360 has 40 divisors (see below), whose sum is σ = 56219616. Its totient is φ = 7253760.

The previous prime is 21157351. The next prime is 21157369. The reversal of 21157360 is 6375112.

It is an interprime number because it is at equal distance from previous prime (21157351) and next prime (21157369).

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21157369) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18331 + ... + 19450.

Almost surely, 2^21157360 is an apocalyptic number.

21157360 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21157360 is an abundant number, since it is smaller than the sum of its proper divisors (35062256).

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

21157360 is a wasteful number, since it uses less digits than its factorization.

21157360 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37801 (or 37795 counting only the distinct ones).

The product of its (nonzero) digits is 1260, while the sum is 25.

The square root of 21157360 is about 4599.7130345273. The cubic root of 21157360 is about 276.5798214544.

The spelling of 21157360 in words is "twenty-one million, one hundred fifty-seven thousand, three hundred sixty".