25915903778 has 18 divisors (see below), whose sum is σ = 39485962971. Its totient is φ = 12757036644.

The previous prime is 25915903763. The next prime is 25915903817. The reversal of 25915903778 is 87730951952.

It can be written as a sum of positive squares in only one way, i.e., 12957951889 + 12957951889 = 113833^2 + 113833^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=113833.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 15252773 + ... + 15254471.

Almost surely, 2^25915903778 is an apocalyptic number.

25915903778 is a deficient number, since it is larger than the sum of its proper divisors (13570059193).

25915903778 is an frugal number, since it uses more digits than its factorization.

25915903778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3534 (or 1768 counting only the distinct ones).

The product of its (nonzero) digits is 4762800, while the sum is 56.

The spelling of 25915903778 in words is "twenty-five billion, nine hundred fifteen million, nine hundred three thousand, seven hundred seventy-eight".