25781315 has 16 divisors (see below), whose sum is σ = 35463360. Its totient is φ = 17625600.

The previous prime is 25781297. The next prime is 25781317. The reversal of 25781315 is 51318752.

It is a de Polignac number, because none of the positive numbers 2^k-25781315 is a prime.

It is not an unprimeable number, because it can be changed into a prime (25781317) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13415 + ... + 15215.

It is an arithmetic number, because the mean of its divisors is an integer number (2216460).

Almost surely, 2^25781315 is an apocalyptic number.

25781315 is a deficient number, since it is larger than the sum of its proper divisors (9682045).

25781315 is a wasteful number, since it uses less digits than its factorization.

25781315 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2222.

The product of its digits is 8400, while the sum is 32.

The square root of 25781315 is about 5077.5304036510. The cubic root of 25781315 is about 295.4166858858.

The spelling of 25781315 in words is "twenty-five million, seven hundred eighty-one thousand, three hundred fifteen".