1331997 has 4 divisors (see below), whose sum is σ = 1776000. Its totient is φ = 887996.

The previous prime is 1331989. The next prime is 1332017. The reversal of 1331997 is 7991331.

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 a cyclic number.

It is not a de Polignac number, because 1331997 - 2³ = 1331989 is a prime.

It is a D-number.

1331997 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1331987) 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, 221997 + ... + 222002.

It is an arithmetic number, because the mean of its divisors is an integer number (444000).

2^1331997 is an apocalyptic number.

It is an amenable number.

1331997 is a deficient number, since it is larger than the sum of its proper divisors (444003).

1331997 is an equidigital number, since it uses as much as digits as its factorization.

1331997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 444002.

The product of its digits is 5103, while the sum is 33.

The square root of 1331997 is about 1154.1217440114. The cubic root of 1331997 is about 110.0274587098.

The spelling of 1331997 in words is "one million, three hundred thirty-one thousand, nine hundred ninety-seven".