25778451687 has 8 divisors (see below), whose sum is σ = 36393108336. Its totient is φ = 16174714752.

The previous prime is 25778451679. The next prime is 25778451719. The reversal of 25778451687 is 78615487752.

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

It is not a de Polignac number, because 25778451687 - 2³ = 25778451679 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 25778451687.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25778451637) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 252729868 + ... + 252729969.

It is an arithmetic number, because the mean of its divisors is an integer number (4549138542).

Almost surely, 2^25778451687 is an apocalyptic number.

25778451687 is a deficient number, since it is larger than the sum of its proper divisors (10614656649).

25778451687 is a wasteful number, since it uses less digits than its factorization.

25778451687 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 505459857.

The product of its digits is 26342400, while the sum is 60.

The spelling of 25778451687 in words is "twenty-five billion, seven hundred seventy-eight million, four hundred fifty-one thousand, six hundred eighty-seven".