21134764 has 24 divisors (see below), whose sum is σ = 44495360. Its totient is φ = 8580816.

The previous prime is 21134761. The next prime is 21134809. The reversal of 21134764 is 46743112.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is not an unprimeable number, because it can be changed into a prime (21134761) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19332 + ... + 20395.

Almost surely, 2^21134764 is an apocalyptic number.

It is an amenable number.

21134764 is an abundant number, since it is smaller than the sum of its proper divisors (23360596).

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

21134764 is a wasteful number, since it uses less digits than its factorization.

21134764 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39757 (or 39755 counting only the distinct ones).

The product of its digits is 4032, while the sum is 28.

The square root of 21134764 is about 4597.2561381763. The cubic root of 21134764 is about 276.4813242283.

Adding to 21134764 its reverse (46743112), we get a palindrome (67877876).

The spelling of 21134764 in words is "twenty-one million, one hundred thirty-four thousand, seven hundred sixty-four".