21669272 has 32 divisors (see below), whose sum is σ = 43935600. Its totient is φ = 9984384.

The previous prime is 21669269. The next prime is 21669281. The reversal of 21669272 is 27296612.

It is a congruent 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 7 ways as a sum of consecutive naturals, for example, 3698 + ... + 7550.

Almost surely, 2^21669272 is an apocalyptic number.

It is an amenable number.

21669272 is an abundant number, since it is smaller than the sum of its proper divisors (22266328).

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

21669272 is a wasteful number, since it uses less digits than its factorization.

21669272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3915 (or 3911 counting only the distinct ones).

The product of its digits is 18144, while the sum is 35.

The square root of 21669272 is about 4655.0265305366. The cubic root of 21669272 is about 278.7927272676.

The spelling of 21669272 in words is "twenty-one million, six hundred sixty-nine thousand, two hundred seventy-two".