25131233621 has 8 divisors (see below), whose sum is σ = 27125505120. Its totient is φ = 23145690672.

The previous prime is 25131233609. The next prime is 25131233623. The reversal of 25131233621 is 12633213152.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-25131233621 is a prime.

It is a super-4 number, since 4×25131233621⁴ (a number of 43 digits) contains 4444 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 (25131233623) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2176151 + ... + 2187668.

It is an arithmetic number, because the mean of its divisors is an integer number (3390688140).

Almost surely, 2^25131233621 is an apocalyptic number.

It is an amenable number.

25131233621 is a deficient number, since it is larger than the sum of its proper divisors (1994271499).

25131233621 is a wasteful number, since it uses less digits than its factorization.

25131233621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4364275.

The product of its digits is 6480, while the sum is 29.

Adding to 25131233621 its reverse (12633213152), we get a palindrome (37764446773).

The spelling of 25131233621 in words is "twenty-five billion, one hundred thirty-one million, two hundred thirty-three thousand, six hundred twenty-one".