779995986 has 64 divisors (see below), whose sum is σ = 1968454656. Its totient is φ = 200145600.

The previous prime is 779995981. The next prime is 779996017. The reversal of 779995986 is 689599977.

It is a super-2 number, since 2×779995986² = 1216787476352224392, which contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 779995986.

It is not an unprimeable number, because it can be changed into a prime (779995981) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 28176 + ... + 48516.

It is an arithmetic number, because the mean of its divisors is an integer number (30757104).

Almost surely, 2^779995986 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 779995986, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (984227328).

779995986 is an abundant number, since it is smaller than the sum of its proper divisors (1188458670).

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

779995986 is a wasteful number, since it uses less digits than its factorization.

779995986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20447.

The product of its digits is 77157360, while the sum is 69.

The square root of 779995986 is about 27928.4082253178. The cubic root of 779995986 is about 920.5148292092.

The spelling of 779995986 in words is "seven hundred seventy-nine million, nine hundred ninety-five thousand, nine hundred eighty-six".