25561926989 has 8 divisors (see below), whose sum is σ = 26108054400. Its totient is φ = 25015893696.

The previous prime is 25561926889. The next prime is 25561927031. The reversal of 25561926989 is 98962916552.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25561926989 is a prime.

It is a super-2 number, since 2×25561926989² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25561926889) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 953237 + ... + 979685.

It is an arithmetic number, because the mean of its divisors is an integer number (3263506800).

Almost surely, 2^25561926989 is an apocalyptic number.

It is an amenable number.

25561926989 is a deficient number, since it is larger than the sum of its proper divisors (546127411).

25561926989 is a wasteful number, since it uses less digits than its factorization.

25561926989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47059.

The product of its digits is 20995200, while the sum is 62.

The spelling of 25561926989 in words is "twenty-five billion, five hundred sixty-one million, nine hundred twenty-six thousand, nine hundred eighty-nine".