21088269 has 12 divisors (see below), whose sum is σ = 31589376. Its totient is φ = 14058684.

The previous prime is 21088241. The next prime is 21088303. The reversal of 21088269 is 96288012.

It is not a de Polignac number, because 21088269 - 2⁵ = 21088237 is a prime.

It is a super-2 number, since 2×21088269² = 889430178832722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21088219) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 43149 + ... + 43634.

It is an arithmetic number, because the mean of its divisors is an integer number (2632448).

Almost surely, 2^21088269 is an apocalyptic number.

It is an amenable number.

21088269 is a deficient number, since it is larger than the sum of its proper divisors (10501107).

21088269 is an frugal number, since it uses more digits than its factorization.

21088269 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86798 (or 86786 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 21088269 is about 4592.1965332507. The cubic root of 21088269 is about 276.2784288563.

The spelling of 21088269 in words is "twenty-one million, eighty-eight thousand, two hundred sixty-nine".