25515251 has 4 divisors (see below), whose sum is σ = 25662912. Its totient is φ = 25367592.

The previous prime is 25515241. The next prime is 25515253. The reversal of 25515251 is 15251552.

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

It is a cyclic number.

It is not a de Polignac number, because 25515251 - 2⁶ = 25515187 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 25515251.

It is not an unprimeable number, because it can be changed into a prime (25515253) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 73571 + ... + 73916.

It is an arithmetic number, because the mean of its divisors is an integer number (6415728).

Almost surely, 2^25515251 is an apocalyptic number.

25515251 is a deficient number, since it is larger than the sum of its proper divisors (147661).

25515251 is a wasteful number, since it uses less digits than its factorization.

25515251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 147660.

The product of its digits is 2500, while the sum is 26.

The square root of 25515251 is about 5051.2623174807. The cubic root of 25515251 is about 294.3969332726.

The spelling of 25515251 in words is "twenty-five million, five hundred fifteen thousand, two hundred fifty-one".