25561783404 has 144 divisors (see below), whose sum is σ = 66980100096. Its totient is φ = 8215084800.

The previous prime is 25561783393. The next prime is 25561783439. The reversal of 25561783404 is 40438716552.

25561783404 is a `hidden beast` number, since 2 + 5 + 561 + 7 + 83 + 4 + 0 + 4 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 25561783404.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 49062664 + ... + 49063184.

It is an arithmetic number, because the mean of its divisors is an integer number (465139584).

Almost surely, 2^25561783404 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 25561783404, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33490050048).

25561783404 is an abundant number, since it is smaller than the sum of its proper divisors (41418316692).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

25561783404 is a wasteful number, since it uses less digits than its factorization.

25561783404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 956 (or 951 counting only the distinct ones).

The product of its (nonzero) digits is 806400, while the sum is 45.

The spelling of 25561783404 in words is "twenty-five billion, five hundred sixty-one million, seven hundred eighty-three thousand, four hundred four".