1591979 has 4 divisors (see below), whose sum is σ = 1598880. Its totient is φ = 1585080.

The previous prime is 1591973. The next prime is 1591981. The reversal of 1591979 is 9791951.

It is a happy number.

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-1591979 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1591973) 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, 3092 + ... + 3569.

It is an arithmetic number, because the mean of its divisors is an integer number (399720).

2^1591979 is an apocalyptic number.

1591979 is a deficient number, since it is larger than the sum of its proper divisors (6901).

1591979 is an equidigital number, since it uses as much as digits as its factorization.

1591979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6900.

The product of its digits is 25515, while the sum is 41.

The square root of 1591979 is about 1261.7365018101. The cubic root of 1591979 is about 116.7649357981.

The spelling of 1591979 in words is "one million, five hundred ninety-one thousand, nine hundred seventy-nine".