25998780806 has 4 divisors (see below), whose sum is σ = 38998171212. Its totient is φ = 12999390402.

The previous prime is 25998780793. The next prime is 25998780827. The reversal of 25998780806 is 60808789952.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6499695200 + ... + 6499695203.

It is an arithmetic number, because the mean of its divisors is an integer number (9749542803).

Almost surely, 2^25998780806 is an apocalyptic number.

25998780806 is a deficient number, since it is larger than the sum of its proper divisors (12999390406).

25998780806 is a wasteful number, since it uses less digits than its factorization.

25998780806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12999390405.

The product of its (nonzero) digits is 17418240, while the sum is 62.

The spelling of 25998780806 in words is "twenty-five billion, nine hundred ninety-eight million, seven hundred eighty thousand, eight hundred six".