25998961361 has 4 divisors (see below), whose sum is σ = 26895477300. Its totient is φ = 25102445424.

The previous prime is 25998961349. The next prime is 25998961399. The reversal of 25998961361 is 16316989952.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 19084041025 + 6914920336 = 138145^2 + 83156^2 .

It is a cyclic number.

It is not a de Polignac number, because 25998961361 - 2¹⁸ = 25998699217 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 25998961361.

It is not an unprimeable number, because it can be changed into a prime (25998961321) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 448257926 + ... + 448257983.

It is an arithmetic number, because the mean of its divisors is an integer number (6723869325).

Almost surely, 2^25998961361 is an apocalyptic number.

It is an amenable number.

25998961361 is a deficient number, since it is larger than the sum of its proper divisors (896515939).

25998961361 is an equidigital number, since it uses as much as digits as its factorization.

25998961361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 896515938.

The product of its digits is 6298560, while the sum is 59.

The spelling of 25998961361 in words is "twenty-five billion, nine hundred ninety-eight million, nine hundred sixty-one thousand, three hundred sixty-one".