25685867779 has 24 divisors (see below), whose sum is σ = 30497489456. Its totient is φ = 21489019200.

The previous prime is 25685867777. The next prime is 25685867789. The reversal of 25685867779 is 97776858652.

It is not a de Polignac number, because 25685867779 - 2¹ = 25685867777 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25685867777) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 495997 + ... + 545329.

Almost surely, 2^25685867779 is an apocalyptic number.

25685867779 is a deficient number, since it is larger than the sum of its proper divisors (4811621677).

25685867779 is a wasteful number, since it uses less digits than its factorization.

25685867779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49699 (or 49688 counting only the distinct ones).

The product of its digits is 355622400, while the sum is 70.

The spelling of 25685867779 in words is "twenty-five billion, six hundred eighty-five million, eight hundred sixty-seven thousand, seven hundred seventy-nine".