21377936 has 10 divisors (see below), whose sum is σ = 41419782. Its totient is φ = 10688960.

The previous prime is 21377929. The next prime is 21377947. The reversal of 21377936 is 63977312.

It can be written as a sum of positive squares in only one way, i.e., 17977600 + 3400336 = 4240^2 + 1844^2 .

It is a super-2 number, since 2×21377936² = 914032295240192, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21377936.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 668045 + ... + 668076.

Almost surely, 2^21377936 is an apocalyptic number.

It is an amenable number.

21377936 is a deficient number, since it is larger than the sum of its proper divisors (20041846).

21377936 is a wasteful number, since it uses less digits than its factorization.

21377936 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1336129 (or 1336123 counting only the distinct ones).

The product of its digits is 47628, while the sum is 38.

The square root of 21377936 is about 4623.6280127190. The cubic root of 21377936 is about 277.5376612035.

The spelling of 21377936 in words is "twenty-one million, three hundred seventy-seven thousand, nine hundred thirty-six".