1979669 has 4 divisors (see below), whose sum is σ = 1982496. Its totient is φ = 1976844.

The previous prime is 1979617. The next prime is 1979683. The reversal of 1979669 is 9669791.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 9669791 = 1889 ⋅5119.

It is a cyclic number.

It is not a de Polignac number, because 1979669 - 2⁸ = 1979413 is a prime.

It is a super-2 number, since 2×1979669² = 7838178699122, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1979609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 512 + ... + 2054.

It is an arithmetic number, because the mean of its divisors is an integer number (495624).

2^1979669 is an apocalyptic number.

It is an amenable number.

1979669 is a deficient number, since it is larger than the sum of its proper divisors (2827).

1979669 is a wasteful number, since it uses less digits than its factorization.

1979669 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2826.

The product of its digits is 183708, while the sum is 47.

The square root of 1979669 is about 1407.0071073026. The cubic root of 1979669 is about 125.5637258833.

The spelling of 1979669 in words is "one million, nine hundred seventy-nine thousand, six hundred sixty-nine".