778998972066 has 32 divisors (see below), whose sum is σ = 1780613265408. Its totient is φ = 222565611600.

The previous prime is 778998971987. The next prime is 778998972067. The reversal of 778998972066 is 660279899877.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 778998971982 and 778998972000.

It is not an unprimeable number, because it can be changed into a prime (778998972067) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1666341 + ... + 2081991.

It is an arithmetic number, because the mean of its divisors is an integer number (55644164544).

Almost surely, 2^778998972066 is an apocalyptic number.

778998972066 is an abundant number, since it is smaller than the sum of its proper divisors (1001614293342).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

778998972066 is a wasteful number, since it uses less digits than its factorization.

778998972066 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 460286.

The product of its (nonzero) digits is 1152216576, while the sum is 78.

The spelling of 778998972066 in words is "seven hundred seventy-eight billion, nine hundred ninety-eight million, nine hundred seventy-two thousand, sixty-six".