21052628 has 12 divisors (see below), whose sum is σ = 37699200. Its totient is φ = 10281432.

The previous prime is 21052621. The next prime is 21052643. The reversal of 21052628 is 82625012.

It is a junction number, because it is equal to n+sod(n) for n = 21052597 and 21052606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21052621) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 61028 + ... + 61371.

It is an arithmetic number, because the mean of its divisors is an integer number (3141600).

Almost surely, 2^21052628 is an apocalyptic number.

It is an amenable number.

21052628 is a deficient number, since it is larger than the sum of its proper divisors (16646572).

21052628 is a wasteful number, since it uses less digits than its factorization.

21052628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122446 (or 122444 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 26.

The square root of 21052628 is about 4588.3142874045. The cubic root of 21052628 is about 276.1226962697.

The spelling of 21052628 in words is "twenty-one million, fifty-two thousand, six hundred twenty-eight".