21536937 has 48 divisors (see below), whose sum is σ = 35006400. Its totient is φ = 12700800.

The previous prime is 21536929. The next prime is 21536939. The reversal of 21536937 is 73963512.

It is not a de Polignac number, because 21536937 - 2³ = 21536929 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (21536939) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 213187 + ... + 213287.

It is an arithmetic number, because the mean of its divisors is an integer number (729300).

Almost surely, 2^21536937 is an apocalyptic number.

It is an amenable number.

21536937 is a deficient number, since it is larger than the sum of its proper divisors (13469463).

21536937 is a wasteful number, since it uses less digits than its factorization.

21536937 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 198 (or 195 counting only the distinct ones).

The product of its digits is 34020, while the sum is 36.

The square root of 21536937 is about 4640.7905576529. The cubic root of 21536937 is about 278.2240357151.

The spelling of 21536937 in words is "twenty-one million, five hundred thirty-six thousand, nine hundred thirty-seven".