21052746 has 48 divisors (see below), whose sum is σ = 53595360. Its totient is φ = 5888160.

The previous prime is 21052739. The next prime is 21052769. The reversal of 21052746 is 64725012.

It is a super-2 number, since 2×21052746² = 886436228281032, which contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1516 + ... + 6663.

It is an arithmetic number, because the mean of its divisors is an integer number (1116570).

Almost surely, 2^21052746 is an apocalyptic number.

21052746 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

21052746 is an abundant number, since it is smaller than the sum of its proper divisors (32542614).

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

21052746 is a wasteful number, since it uses less digits than its factorization.

21052746 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8211 (or 8208 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 27.

The square root of 21052746 is about 4588.3271461394. The cubic root of 21052746 is about 276.1232121581.

Adding to 21052746 its reverse (64725012), we get a palindrome (85777758).

It can be divided in two parts, 2105 and 2746, that added together give a triangular number (4851 = T₉₈).

The spelling of 21052746 in words is "twenty-one million, fifty-two thousand, seven hundred forty-six".