2123819 has 4 divisors (see below), whose sum is σ = 2130960. Its totient is φ = 2116680.

The previous prime is 2123791. The next prime is 2123831. The reversal of 2123819 is 9183212.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2123819 is a prime.

It is a super-2 number, since 2×2123819² = 9021214289522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2123879) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3104 + ... + 3725.

It is an arithmetic number, because the mean of its divisors is an integer number (532740).

2^2123819 is an apocalyptic number.

2123819 is a deficient number, since it is larger than the sum of its proper divisors (7141).

2123819 is an equidigital number, since it uses as much as digits as its factorization.

2123819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7140.

The product of its digits is 864, while the sum is 26.

The square root of 2123819 is about 1457.3328377553. The cubic root of 2123819 is about 128.5402579934.

It can be divided in two parts, 212 and 3819, that multiplied together give a triangular number (809628 = T₁₂₇₂).

The spelling of 2123819 in words is "two million, one hundred twenty-three thousand, eight hundred nineteen".