1979823 has 4 divisors (see below), whose sum is σ = 2639768. Its totient is φ = 1319880.

The previous prime is 1979807. The next prime is 1979827. The reversal of 1979823 is 3289791.

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

It is not a de Polignac number, because 1979823 - 2⁴ = 1979807 is a prime.

It is a super-2 number, since 2×1979823² = 7839398222658, which contains 22 as substring.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1979827) 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, 329968 + ... + 329973.

It is an arithmetic number, because the mean of its divisors is an integer number (659942).

2^1979823 is an apocalyptic number.

1979823 is a deficient number, since it is larger than the sum of its proper divisors (659945).

1979823 is an equidigital number, since it uses as much as digits as its factorization.

1979823 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 659944.

The product of its digits is 27216, while the sum is 39.

The square root of 1979823 is about 1407.0618323301. The cubic root of 1979823 is about 125.5669816990.

The spelling of 1979823 in words is "one million, nine hundred seventy-nine thousand, eight hundred twenty-three".