2109787279 has 4 divisors (see below), whose sum is σ = 2110286680. Its totient is φ = 2109287880.

The previous prime is 2109787237. The next prime is 2109787301. The reversal of 2109787279 is 9727879012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2109787279 - 2²⁷ = 1975569551 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 (2109787579) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 243309 + ... + 251830.

It is an arithmetic number, because the mean of its divisors is an integer number (527571670).

Almost surely, 2^2109787279 is an apocalyptic number.

2109787279 is a deficient number, since it is larger than the sum of its proper divisors (499401).

2109787279 is an equidigital number, since it uses as much as digits as its factorization.

2109787279 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 499400.

The product of its (nonzero) digits is 889056, while the sum is 52.

The square root of 2109787279 is about 45932.4207831462. The cubic root of 2109787279 is about 1282.5655085999.

The spelling of 2109787279 in words is "two billion, one hundred nine million, seven hundred eighty-seven thousand, two hundred seventy-nine".