25631940649 has 8 divisors (see below), whose sum is σ = 29974894400. Its totient is φ = 21459298896.

The previous prime is 25631940619. The next prime is 25631940683. The reversal of 25631940649 is 94604913652.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 25631940649 - 2⁹ = 25631940137 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25631940619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 42577674 + ... + 42578275.

It is an arithmetic number, because the mean of its divisors is an integer number (3746861800).

Almost surely, 2^25631940649 is an apocalyptic number.

It is an amenable number.

25631940649 is a deficient number, since it is larger than the sum of its proper divisors (4342953751).

25631940649 is an equidigital number, since it uses as much as digits as its factorization.

25631940649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85155999.

The product of its (nonzero) digits is 1399680, while the sum is 49.

The spelling of 25631940649 in words is "twenty-five billion, six hundred thirty-one million, nine hundred forty thousand, six hundred forty-nine".