25659700993 has 4 divisors (see below), whose sum is σ = 25740646740. Its totient is φ = 25578755248.

The previous prime is 25659700991. The next prime is 25659700999. The reversal of 25659700993 is 39900795652.

It is a happy number.

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 427331584 + 25232369409 = 20672^2 + 158847^2 .

It is a cyclic number.

It is not a de Polignac number, because 25659700993 - 2¹ = 25659700991 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25659700991) 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, 40472398 + ... + 40473031.

It is an arithmetic number, because the mean of its divisors is an integer number (6435161685).

Almost surely, 2^25659700993 is an apocalyptic number.

It is an amenable number.

25659700993 is a deficient number, since it is larger than the sum of its proper divisors (80945747).

25659700993 is an equidigital number, since it uses as much as digits as its factorization.

25659700993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80945746.

The product of its (nonzero) digits is 4592700, while the sum is 55.

The spelling of 25659700993 in words is "twenty-five billion, six hundred fifty-nine million, seven hundred thousand, nine hundred ninety-three".