25505278025 has 24 divisors (see below), whose sum is σ = 31935612984. Its totient is φ = 20205158400.

The previous prime is 25505278009. The next prime is 25505278061. The reversal of 25505278025 is 52087250552.

It can be written as a sum of positive squares in 12 ways, for example, as 2919997369 + 22585280656 = 54037^2 + 150284^2 .

It is not a de Polignac number, because 25505278025 - 2⁴ = 25505278009 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3660545 + ... + 3667505.

It is an arithmetic number, because the mean of its divisors is an integer number (1330650541).

Almost surely, 2^25505278025 is an apocalyptic number.

25505278025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

25505278025 is a deficient number, since it is larger than the sum of its proper divisors (6430334959).

25505278025 is a wasteful number, since it uses less digits than its factorization.

25505278025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8381 (or 8376 counting only the distinct ones).

The product of its (nonzero) digits is 280000, while the sum is 41.

It can be divided in two parts, 2550527 and 8025, that added together give a palindrome (2558552).

The spelling of 25505278025 in words is "twenty-five billion, five hundred five million, two hundred seventy-eight thousand, twenty-five".