21053132 has 18 divisors (see below), whose sum is σ = 37268028. Its totient is φ = 10406448.

The previous prime is 21053129. The next prime is 21053173. The reversal of 21053132 is 23135012.

It is a self number, because there is not a number n which added to its sum of digits gives 21053132.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 47303 + ... + 47745.

It is an arithmetic number, because the mean of its divisors is an integer number (2070446).

Almost surely, 2^21053132 is an apocalyptic number.

It is an amenable number.

21053132 is a deficient number, since it is larger than the sum of its proper divisors (16214896).

21053132 is a wasteful number, since it uses less digits than its factorization.

21053132 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 665 (or 554 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 17.

The square root of 21053132 is about 4588.3692092071. The cubic root of 21053132 is about 276.1248997116.

Adding to 21053132 its reverse (23135012), we get a palindrome (44188144).

The spelling of 21053132 in words is "twenty-one million, fifty-three thousand, one hundred thirty-two".