1991079 has 12 divisors (see below), whose sum is σ = 2893176. Its totient is φ = 1319472.

The previous prime is 1991071. The next prime is 1991089. The reversal of 1991079 is 9701991.

1991079 is nontrivially palindromic in base 8.

It is not a de Polignac number, because 1991079 - 2³ = 1991071 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1991071) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1212 + ... + 2334.

It is an arithmetic number, because the mean of its divisors is an integer number (241098).

2^1991079 is an apocalyptic number.

1991079 is a deficient number, since it is larger than the sum of its proper divisors (902097).

1991079 is a wasteful number, since it uses less digits than its factorization.

1991079 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1326 (or 1323 counting only the distinct ones).

The product of its (nonzero) digits is 5103, while the sum is 36.

The square root of 1991079 is about 1411.0559875497. The cubic root of 1991079 is about 125.8044965084.

The spelling of 1991079 in words is "one million, nine hundred ninety-one thousand, seventy-nine".