21137652 has 48 divisors (see below), whose sum is σ = 57691200. Its totient is φ = 6674400.

The previous prime is 21137609. The next prime is 21137657. The reversal of 21137652 is 25673112.

It is a happy number.

21137652 is a `hidden beast` number, since 2 + 1 + 1 + 3 + 7 + 652 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21137657) 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, 3099 + ... + 7202.

It is an arithmetic number, because the mean of its divisors is an integer number (1201900).

Almost surely, 2^21137652 is an apocalyptic number.

It is an amenable number.

21137652 is an abundant number, since it is smaller than the sum of its proper divisors (36553548).

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

21137652 is a wasteful number, since it uses less digits than its factorization.

21137652 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10333 (or 10325 counting only the distinct ones).

The product of its digits is 2520, while the sum is 27.

The square root of 21137652 is about 4597.5702278486. The cubic root of 21137652 is about 276.4939170934.

The spelling of 21137652 in words is "twenty-one million, one hundred thirty-seven thousand, six hundred fifty-two".