21655132 has 12 divisors (see below), whose sum is σ = 38265136. Its totient is φ = 10722240.

The previous prime is 21655129. The next prime is 21655147. The reversal of 21655132 is 23155612.

It is a hoax number, since the sum of its digits (25) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 21655097 and 21655106.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 25869 + ... + 26692.

Almost surely, 2^21655132 is an apocalyptic number.

It is an amenable number.

21655132 is a deficient number, since it is larger than the sum of its proper divisors (16610004).

21655132 is a wasteful number, since it uses less digits than its factorization.

21655132 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52668 (or 52666 counting only the distinct ones).

The product of its digits is 1800, while the sum is 25.

The square root of 21655132 is about 4653.5074943530. The cubic root of 21655132 is about 278.7320732236.

The spelling of 21655132 in words is "twenty-one million, six hundred fifty-five thousand, one hundred thirty-two".