25897447493 has 2 divisors, whose sum is σ = 25897447494. Its totient is φ = 25897447492.

The previous prime is 25897447453. The next prime is 25897447531. The reversal of 25897447493 is 39474479852.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25841527009 + 55920484 = 160753^2 + 7478^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25897447493 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25897447453) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12948723746 + 12948723747.

It is an arithmetic number, because the mean of its divisors is an integer number (12948723747).

Almost surely, 2^25897447493 is an apocalyptic number.

It is an amenable number.

25897447493 is a deficient number, since it is larger than the sum of its proper divisors (1).

25897447493 is an equidigital number, since it uses as much as digits as its factorization.

25897447493 is an evil number, because the sum of its binary digits is even.

The product of its digits is 60963840, while the sum is 62.

The spelling of 25897447493 in words is "twenty-five billion, eight hundred ninety-seven million, four hundred forty-seven thousand, four hundred ninety-three".