1399495778 has 16 divisors (see below), whose sum is σ = 2109414264. Its totient is φ = 696366720.

The previous prime is 1399495751. The next prime is 1399495817. The reversal of 1399495778 is 8775949931.

It can be written as a sum of positive squares in 4 ways, for example, as 599907049 + 799588729 = 24493^2 + 28277^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1399495778.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 382976 + ... + 386612.

Almost surely, 2^1399495778 is an apocalyptic number.

1399495778 is a deficient number, since it is larger than the sum of its proper divisors (709918486).

1399495778 is a wasteful number, since it uses less digits than its factorization.

1399495778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4517.

The product of its digits is 17146080, while the sum is 62.

The square root of 1399495778 is about 37409.8353110516. The cubic root of 1399495778 is about 1118.5546241511.

The spelling of 1399495778 in words is "one billion, three hundred ninety-nine million, four hundred ninety-five thousand, seven hundred seventy-eight".