109779 has 16 divisors (see below), whose sum is σ = 160512. Its totient is φ = 66528.

The previous prime is 109751. The next prime is 109789. The reversal of 109779 is 977901.

It is not a de Polignac number, because 109779 - 2⁹ = 109267 is a prime.

109779 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (109789) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2532 + ... + 2574.

It is an arithmetic number, because the mean of its divisors is an integer number (10032).

2¹⁰⁹⁷⁷⁹ is an apocalyptic number.

109779 is a deficient number, since it is larger than the sum of its proper divisors (50733).

109779 is a wasteful number, since it uses less digits than its factorization.

109779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106.

The product of its (nonzero) digits is 3969, while the sum is 33.

The square root of 109779 is about 331.3291414892. The cubic root of 109779 is about 47.8820890638.

Subtracting from 109779 its sum of digits (33), we obtain a triangular number (109746 = T₄₆₈).

It can be divided in two parts, 1097 and 79, that added together give a triangular number (1176 = T₄₈).

The spelling of 109779 in words is "one hundred nine thousand, seven hundred seventy-nine".