25172386851 has 4 divisors (see below), whose sum is σ = 33563182472. Its totient is φ = 16781591232.

The previous prime is 25172386807. The next prime is 25172386859. The reversal of 25172386851 is 15868327152.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 25172386851 - 2¹³ = 25172378659 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 25172386851.

It is not an unprimeable number, because it can be changed into a prime (25172386859) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4195397806 + ... + 4195397811.

It is an arithmetic number, because the mean of its divisors is an integer number (8390795618).

Almost surely, 2^25172386851 is an apocalyptic number.

25172386851 is a deficient number, since it is larger than the sum of its proper divisors (8390795621).

25172386851 is an equidigital number, since it uses as much as digits as its factorization.

25172386851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8390795620.

The product of its digits is 806400, while the sum is 48.

The spelling of 25172386851 in words is "twenty-five billion, one hundred seventy-two million, three hundred eighty-six thousand, eight hundred fifty-one".