1597989 has 4 divisors (see below), whose sum is σ = 2130656. Its totient is φ = 1065324.

The previous prime is 1597979. The next prime is 1598011. The reversal of 1597989 is 9897951.

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.

It is not a de Polignac number, because 1597989 - 2⁷ = 1597861 is a prime.

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 (1597969) 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, 266329 + ... + 266334.

It is an arithmetic number, because the mean of its divisors is an integer number (532664).

2^1597989 is an apocalyptic number.

It is an amenable number.

1597989 is a deficient number, since it is larger than the sum of its proper divisors (532667).

1597989 is an equidigital number, since it uses as much as digits as its factorization.

1597989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 532666.

The product of its digits is 204120, while the sum is 48.

The square root of 1597989 is about 1264.1158965854. The cubic root of 1597989 is about 116.9116873206.

The spelling of 1597989 in words is "one million, five hundred ninety-seven thousand, nine hundred eighty-nine".