25810880721 has 8 divisors (see below), whose sum is σ = 34416251520. Its totient is φ = 17206381872.

The previous prime is 25810880713. The next prime is 25810880723. The reversal of 25810880721 is 12708801852.

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

It is not a de Polignac number, because 25810880721 - 2³ = 25810880713 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (25810880723) 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, 145470 + ... + 269783.

It is an arithmetic number, because the mean of its divisors is an integer number (4302031440).

Almost surely, 2^25810880721 is an apocalyptic number.

It is an amenable number.

25810880721 is a deficient number, since it is larger than the sum of its proper divisors (8605370799).

25810880721 is a wasteful number, since it uses less digits than its factorization.

25810880721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 435975.

The product of its (nonzero) digits is 71680, while the sum is 42.

It can be divided in two parts, 25810 and 880721, that added together give a triangular number (906531 = T₁₃₄₆).

The spelling of 25810880721 in words is "twenty-five billion, eight hundred ten million, eight hundred eighty thousand, seven hundred twenty-one".