25172621 has 4 divisors (see below), whose sum is σ = 25280892. Its totient is φ = 25064352.

The previous prime is 25172611. The next prime is 25172627. The reversal of 25172621 is 12627152.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4141225 + 21031396 = 2035^2 + 4586^2 .

It is a cyclic number.

It is not a de Polignac number, because 25172621 - 2²² = 20978317 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25172627) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53786 + ... + 54251.

It is an arithmetic number, because the mean of its divisors is an integer number (6320223).

Almost surely, 2^25172621 is an apocalyptic number.

It is an amenable number.

25172621 is a deficient number, since it is larger than the sum of its proper divisors (108271).

25172621 is a wasteful number, since it uses less digits than its factorization.

25172621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108270.

The product of its digits is 1680, while the sum is 26.

The square root of 25172621 is about 5017.2324044238. The cubic root of 25172621 is about 293.0732265811.

Adding to 25172621 its reverse (12627152), we get a palindrome (37799773).

The spelling of 25172621 in words is "twenty-five million, one hundred seventy-two thousand, six hundred twenty-one".