21134636 has 12 divisors (see below), whose sum is σ = 37017960. Its totient is φ = 10558080.

The previous prime is 21134611. The next prime is 21134657. The reversal of 21134636 is 63643112.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7055 + ... + 9593.

It is an arithmetic number, because the mean of its divisors is an integer number (3084830).

Almost surely, 2^21134636 is an apocalyptic number.

It is an amenable number.

21134636 is a deficient number, since it is larger than the sum of its proper divisors (15883324).

21134636 is a wasteful number, since it uses less digits than its factorization.

21134636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4624 (or 4622 counting only the distinct ones).

The product of its digits is 2592, while the sum is 26.

The square root of 21134636 is about 4597.2422168078. The cubic root of 21134636 is about 276.4807660692.

Adding to 21134636 its reverse (63643112), we get a palindrome (84777748).

The spelling of 21134636 in words is "twenty-one million, one hundred thirty-four thousand, six hundred thirty-six".