251327820778 has 8 divisors (see below), whose sum is σ = 376999256772. Its totient is φ = 125661401856.

The previous prime is 251327820761. The next prime is 251327820787. The reversal of 251327820778 is 877028723152.

251327820778 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 170596259089 + 80731561689 = 413033^2 + 284133^2 .

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

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 1126425 + ... + 1330972.

Almost surely, 2^251327820778 is an apocalyptic number.

251327820778 is a deficient number, since it is larger than the sum of its proper divisors (125671435994).

251327820778 is a wasteful number, since it uses less digits than its factorization.

251327820778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2508536.

The product of its (nonzero) digits is 2634240, while the sum is 52.

The spelling of 251327820778 in words is "two hundred fifty-one billion, three hundred twenty-seven million, eight hundred twenty thousand, seven hundred seventy-eight".