21053286 has 12 divisors (see below), whose sum is σ = 45615492. Its totient is φ = 7017756.

The previous prime is 21053281. The next prime is 21053287. The reversal of 21053286 is 68235012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21053281) 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 5 ways as a sum of consecutive naturals, for example, 584796 + ... + 584831.

It is an arithmetic number, because the mean of its divisors is an integer number (3801291).

Almost surely, 2^21053286 is an apocalyptic number.

21053286 is an abundant number, since it is smaller than the sum of its proper divisors (24562206).

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

21053286 is a wasteful number, since it uses less digits than its factorization.

21053286 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1169635 (or 1169632 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 21053286 is about 4588.3859907379. The cubic root of 21053286 is about 276.1255729785.

Adding to 21053286 its reverse (68235012), we get a palindrome (89288298).

The spelling of 21053286 in words is "twenty-one million, fifty-three thousand, two hundred eighty-six".