21130125 has 48 divisors (see below), whose sum is σ = 36958272. Its totient is φ = 10718400.

The previous prime is 21130111. The next prime is 21130231. The reversal of 21130125 is 52103112.

It is not a de Polignac number, because 21130125 - 2⁸ = 21129869 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 315342 + ... + 315408.

It is an arithmetic number, because the mean of its divisors is an integer number (769964).

Almost surely, 2^21130125 is an apocalyptic number.

21130125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21130125 is a deficient number, since it is larger than the sum of its proper divisors (15828147).

21130125 is an equidigital number, since it uses as much as digits as its factorization.

21130125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143 (or 104 counting only the distinct ones).

The product of its (nonzero) digits is 60, while the sum is 15.

The square root of 21130125 is about 4596.7515704027. The cubic root of 21130125 is about 276.4610938830.

Adding to 21130125 its reverse (52103112), we get a palindrome (73233237).

The spelling of 21130125 in words is "twenty-one million, one hundred thirty thousand, one hundred twenty-five".