25615682401 has 3 divisors (see below), whose sum is σ = 25615842451. Its totient is φ = 25615522352.

The previous prime is 25615682387. The next prime is 25615682419. The reversal of 25615682401 is 10428651652.

The square root of 25615682401 is 160049.

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

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 25584322401 + 31360000 = 159951^2 + 5600^2 .

It is not a de Polignac number, because 25615682401 - 2⁵ = 25615682369 is a prime.

It is a super-2 number, since 2×25615682401² (a number of 22 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25615682461) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 80025 + ... + 240073.

Almost surely, 2^25615682401 is an apocalyptic number.

25615682401 is the 160049-th square number.

25615682401 is the 80025-th centered octagonal number.

It is an amenable number.

25615682401 is a deficient number, since it is larger than the sum of its proper divisors (160050).

25615682401 is an frugal number, since it uses more digits than its factorization.

25615682401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 320098 (or 160049 counting only the distinct ones).

The product of its (nonzero) digits is 115200, while the sum is 40.

The spelling of 25615682401 in words is "twenty-five billion, six hundred fifteen million, six hundred eighty-two thousand, four hundred one".