21010736 has 10 divisors (see below), whose sum is σ = 40708332. Its totient is φ = 10505360.

The previous prime is 21010733. The next prime is 21010741. The reversal of 21010736 is 63701012.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21010733) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 656570 + ... + 656601.

Almost surely, 2^21010736 is an apocalyptic number.

It is an amenable number.

21010736 is a deficient number, since it is larger than the sum of its proper divisors (19697596).

21010736 is a wasteful number, since it uses less digits than its factorization.

21010736 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1313179 (or 1313173 counting only the distinct ones).

The product of its (nonzero) digits is 252, while the sum is 20.

The square root of 21010736 is about 4583.7469389136. The cubic root of 21010736 is about 275.9394251997.

Adding to 21010736 its reverse (63701012), we get a palindrome (84711748).

The spelling of 21010736 in words is "twenty-one million, ten thousand, seven hundred thirty-six".