21158700 has 36 divisors (see below), whose sum is σ = 61220040. Its totient is φ = 5642240.

The previous prime is 21158677. The next prime is 21158701. The reversal of 21158700 is 785112.

It is not an unprimeable number, because it can be changed into a prime (21158701) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 34965 + ... + 35564.

Almost surely, 2^21158700 is an apocalyptic number.

21158700 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21158700 is an abundant number, since it is smaller than the sum of its proper divisors (40061340).

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

21158700 is a wasteful number, since it uses less digits than its factorization.

21158700 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70546 (or 70539 counting only the distinct ones).

The product of its (nonzero) digits is 560, while the sum is 24.

The square root of 21158700 is about 4599.8586934818. The cubic root of 21158700 is about 276.5856603860.

The spelling of 21158700 in words is "twenty-one million, one hundred fifty-eight thousand, seven hundred".