21267725 has 12 divisors (see below), whose sum is σ = 27016500. Its totient is φ = 16598400.

The previous prime is 21267721. The next prime is 21267737. The reversal of 21267725 is 52776212.

It can be written as a sum of positive squares in 6 ways, for example, as 9523396 + 11744329 = 3086^2 + 3427^2 .

It is not a de Polignac number, because 21267725 - 2² = 21267721 is a prime.

It is a super-2 number, since 2×21267725² = 904632253351250, which contains 22 as substring.

It is a hoax number, since the sum of its digits (32) 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 = 21267691 and 21267700.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21267721) 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, 9350 + ... + 11399.

It is an arithmetic number, because the mean of its divisors is an integer number (2251375).

Almost surely, 2^21267725 is an apocalyptic number.

21267725 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21267725 is a deficient number, since it is larger than the sum of its proper divisors (5748775).

21267725 is a wasteful number, since it uses less digits than its factorization.

21267725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20800 (or 20795 counting only the distinct ones).

The product of its digits is 11760, while the sum is 32.

The square root of 21267725 is about 4611.6943740886. The cubic root of 21267725 is about 277.0599035471.

The spelling of 21267725 in words is "twenty-one million, two hundred sixty-seven thousand, seven hundred twenty-five".