25539507198 has 80 divisors (see below), whose sum is σ = 59914950480. Its totient is φ = 8120456064.

The previous prime is 25539507193. The next prime is 25539507277. The reversal of 25539507198 is 89170593552.

25539507198 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×25539507198² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25539507193) 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 39 ways as a sum of consecutive naturals, for example, 357186 + ... + 422682.

It is an arithmetic number, because the mean of its divisors is an integer number (748936881).

Almost surely, 2^25539507198 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 25539507198, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29957475240).

25539507198 is an abundant number, since it is smaller than the sum of its proper divisors (34375443282).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

25539507198 is a wasteful number, since it uses less digits than its factorization.

25539507198 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65623 (or 65614 counting only the distinct ones).

The product of its (nonzero) digits is 3402000, while the sum is 54.

The spelling of 25539507198 in words is "twenty-five billion, five hundred thirty-nine million, five hundred seven thousand, one hundred ninety-eight".