25747090681 has 9 divisors (see below), whose sum is σ = 27882244719. Its totient is φ = 23764619736.

The previous prime is 25747090667. The next prime is 25747090717. The reversal of 25747090681 is 18609074752.

The square root of 25747090681 is 160459.

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

It can be written as a sum of positive squares in only one way, i.e., 3808741225 + 21938349456 = 61715^2 + 148116^2 .

It is not a de Polignac number, because 25747090681 - 2⁷ = 25747090553 is a prime.

It is a super-2 number, since 2×25747090681² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25747090601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 2079796 + ... + 2092138.

It is an arithmetic number, because the mean of its divisors is an integer number (3098027191).

Almost surely, 2^25747090681 is an apocalyptic number.

25747090681 is the 160459-th square number.

25747090681 is the 80230-th centered octagonal number.

It is an amenable number.

25747090681 is a deficient number, since it is larger than the sum of its proper divisors (2135154038).

25747090681 is an frugal number, since it uses more digits than its factorization.

25747090681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24712 (or 12356 counting only the distinct ones).

The product of its (nonzero) digits is 846720, while the sum is 49.

Multiplying 25747090681 by its sum of digits (49), we get a square (1261607443369 = 1123213²).

The spelling of 25747090681 in words is "twenty-five billion, seven hundred forty-seven million, ninety thousand, six hundred eighty-one".