21169125 has 48 divisors (see below), whose sum is σ = 39456768. Its totient is φ = 10908000.

The previous prime is 21169121. The next prime is 21169139. The reversal of 21169125 is 52196112.

It is not a de Polignac number, because 21169125 - 2² = 21169121 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21169121) by changing a digit.

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 47 ways as a sum of consecutive naturals, for example, 34572 + ... + 35178.

It is an arithmetic number, because the mean of its divisors is an integer number (822016).

Almost surely, 2^21169125 is an apocalyptic number.

21169125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21169125 is a deficient number, since it is larger than the sum of its proper divisors (18287643).

21169125 is a wasteful number, since it uses less digits than its factorization.

21169125 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 659 (or 646 counting only the distinct ones).

The product of its digits is 1080, while the sum is 27.

The square root of 21169125 is about 4600.9917409185. The cubic root of 21169125 is about 276.6310779855.

The spelling of 21169125 in words is "twenty-one million, one hundred sixty-nine thousand, one hundred twenty-five".