2123779 has 8 divisors (see below), whose sum is σ = 2505728. Its totient is φ = 1761480.

The previous prime is 2123777. The next prime is 2123783. The reversal of 2123779 is 9773212.

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

It is not a de Polignac number, because 2123779 - 2¹ = 2123777 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a d-powerful number, because it can be written as 2⁷ + 1 + 2²¹ + 3⁸ + 7⁴ + 7⁵ + 9³ .

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2123779.

It is not an unprimeable number, because it can be changed into a prime (2123773) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4677 + ... + 5110.

It is an arithmetic number, because the mean of its divisors is an integer number (313216).

2^2123779 is an apocalyptic number.

2123779 is a deficient number, since it is larger than the sum of its proper divisors (381949).

2123779 is an equidigital number, since it uses as much as digits as its factorization.

2123779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9825.

The product of its digits is 5292, while the sum is 31.

The square root of 2123779 is about 1457.3191139898. The cubic root of 2123779 is about 128.5394510127.

It can be divided in two parts, 21237 and 79, that added together give a square (21316 = 146²).

The spelling of 2123779 in words is "two million, one hundred twenty-three thousand, seven hundred seventy-nine".