21413125 has 10 divisors (see below), whose sum is σ = 26758622. Its totient is φ = 17130000.

The previous prime is 21413123. The next prime is 21413131. The reversal of 21413125 is 52131412.

It can be written as a sum of positive squares in 5 ways, for example, as 2070721 + 19342404 = 1439^2 + 4398^2 .

It is not a de Polignac number, because 21413125 - 2¹ = 21413123 is a prime.

It is a super-3 number, since 3×21413125³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21413123) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 16506 + ... + 17755.

Almost surely, 2^21413125 is an apocalyptic number.

21413125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21413125 is a deficient number, since it is larger than the sum of its proper divisors (5345497).

21413125 is an frugal number, since it uses more digits than its factorization.

21413125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34281 (or 34266 counting only the distinct ones).

The product of its digits is 240, while the sum is 19.

The square root of 21413125 is about 4627.4317931224. The cubic root of 21413125 is about 277.6898573601.

Adding to 21413125 its reverse (52131412), we get a palindrome (73544537).

The spelling of 21413125 in words is "twenty-one million, four hundred thirteen thousand, one hundred twenty-five".