21124125 has 64 divisors (see below), whose sum is σ = 42681600. Its totient is φ = 10224000.

The previous prime is 21124123. The next prime is 21124141. The reversal of 21124125 is 52142112.

It is not a de Polignac number, because 21124125 - 2¹ = 21124123 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21124098 and 21124107.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21124123) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 36841 + ... + 37409.

It is an arithmetic number, because the mean of its divisors is an integer number (666900).

Almost surely, 2^21124125 is an apocalyptic number.

21124125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21124125 is an abundant number, since it is smaller than the sum of its proper divisors (21557475).

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

21124125 is a wasteful number, since it uses less digits than its factorization.

21124125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 604 (or 588 counting only the distinct ones).

The product of its digits is 160, while the sum is 18.

The square root of 21124125 is about 4596.0988892756. The cubic root of 21124125 is about 276.4349239228.

Adding to 21124125 its reverse (52142112), we get a palindrome (73266237).

It can be divided in two parts, 211 and 24125, that added together give a square (24336 = 156²).

The spelling of 21124125 in words is "twenty-one million, one hundred twenty-four thousand, one hundred twenty-five".