25641307949 has 4 divisors (see below), whose sum is σ = 25641718464. Its totient is φ = 25640897436.

The previous prime is 25641307931. The next prime is 25641307987. The reversal of 25641307949 is 94970314652.

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 25641307949 - 2⁸ = 25641307693 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 25641307897 and 25641307906.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25641307999) 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, 89987 + ... + 243680.

It is an arithmetic number, because the mean of its divisors is an integer number (6410429616).

Almost surely, 2^25641307949 is an apocalyptic number.

It is an amenable number.

25641307949 is a deficient number, since it is larger than the sum of its proper divisors (410515).

25641307949 is an equidigital number, since it uses as much as digits as its factorization.

25641307949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 410514.

The product of its (nonzero) digits is 1632960, while the sum is 50.

The spelling of 25641307949 in words is "twenty-five billion, six hundred forty-one million, three hundred seven thousand, nine hundred forty-nine".