25257946991 has 2 divisors, whose sum is σ = 25257946992. Its totient is φ = 25257946990.

The previous prime is 25257946957. The next prime is 25257947059. The reversal of 25257946991 is 19964975252.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 25257946991 - 2²² = 25253752687 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 25257946991.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25257946391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12628973495 + 12628973496.

It is an arithmetic number, because the mean of its divisors is an integer number (12628973496).

Almost surely, 2^25257946991 is an apocalyptic number.

25257946991 is a deficient number, since it is larger than the sum of its proper divisors (1).

25257946991 is an equidigital number, since it uses as much as digits as its factorization.

25257946991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12247200, while the sum is 59.

The spelling of 25257946991 in words is "twenty-five billion, two hundred fifty-seven million, nine hundred forty-six thousand, nine hundred ninety-one".