2166780013 has 8 divisors (see below), whose sum is σ = 2220273720. Its totient is φ = 2113317120.

The previous prime is 2166779959. The next prime is 2166780023. The reversal of 2166780013 is 3100876612.

It can be written as a sum of positive squares in 4 ways, for example, as 258662889 + 1908117124 = 16083^2 + 43682^2 .

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

It is not a de Polignac number, because 2166780013 - 2²⁵ = 2133225581 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2166780023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 207993 + ... + 218161.

It is an arithmetic number, because the mean of its divisors is an integer number (277534215).

Almost surely, 2^2166780013 is an apocalyptic number.

It is an amenable number.

2166780013 is a deficient number, since it is larger than the sum of its proper divisors (53493707).

2166780013 is a wasteful number, since it uses less digits than its factorization.

2166780013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15407.

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 2166780013 is about 46548.6843315684. The cubic root of 2166780013 is about 1294.0119101694.

The spelling of 2166780013 in words is "two billion, one hundred sixty-six million, seven hundred eighty thousand, thirteen".