25581906977 has 4 divisors (see below), whose sum is σ = 27907534896. Its totient is φ = 23256279060.

The previous prime is 25581906949. The next prime is 25581906997. The reversal of 25581906977 is 77960918552.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 25581906977 - 2¹⁸ = 25581644833 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25581906997) 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, 1162813943 + ... + 1162813964.

It is an arithmetic number, because the mean of its divisors is an integer number (6976883724).

Almost surely, 2^25581906977 is an apocalyptic number.

It is an amenable number.

25581906977 is a deficient number, since it is larger than the sum of its proper divisors (2325627919).

25581906977 is a wasteful number, since it uses less digits than its factorization.

25581906977 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2325627918.

The product of its (nonzero) digits is 9525600, while the sum is 59.

The spelling of 25581906977 in words is "twenty-five billion, five hundred eighty-one million, nine hundred six thousand, nine hundred seventy-seven".