25631049409 has 9 divisors (see below), whose sum is σ = 29817014241. Its totient is φ = 21968510340.

The previous prime is 25631049397. The next prime is 25631049443. The reversal of 25631049409 is 90494013652.

The square root of 25631049409 is 160097.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 25631049409 - 2¹¹ = 25631047361 is a prime.

It is not an unprimeable number, because it can be changed into a prime (25631049469) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1109244 + ... + 1132114.

Almost surely, 2^25631049409 is an apocalyptic number.

25631049409 is the 160097-th square number.

25631049409 is the 80049-th centered octagonal number.

It is an amenable number.

25631049409 is a deficient number, since it is larger than the sum of its proper divisors (4185964832).

25631049409 is an frugal number, since it uses more digits than its factorization.

25631049409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45756 (or 22878 counting only the distinct ones).

The product of its (nonzero) digits is 233280, while the sum is 43.

The spelling of 25631049409 in words is "twenty-five billion, six hundred thirty-one million, forty-nine thousand, four hundred nine".