8211613778 has 32 divisors (see below), whose sum is σ = 13006417536. Its totient is φ = 3880597248.

The previous prime is 8211613763. The next prime is 8211613793. The reversal of 8211613778 is 8773161128.

It is an interprime number because it is at equal distance from previous prime (8211613763) and next prime (8211613793).

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2129300 + ... + 2133152.

It is an arithmetic number, because the mean of its divisors is an integer number (406450548).

Almost surely, 2^8211613778 is an apocalyptic number.

8211613778 is a deficient number, since it is larger than the sum of its proper divisors (4794803758).

8211613778 is a wasteful number, since it uses less digits than its factorization.

8211613778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4418.

The product of its digits is 112896, while the sum is 44.

The square root of 8211613778 is about 90617.9550530688. The cubic root of 8211613778 is about 2017.4812394538.

The spelling of 8211613778 in words is "eight billion, two hundred eleven million, six hundred thirteen thousand, seven hundred seventy-eight".