1897189 has 4 divisors (see below), whose sum is σ = 2168224. Its totient is φ = 1626156.

The previous prime is 1897177. The next prime is 1897199. The reversal of 1897189 is 9817981.

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 1897189 - 2⁹ = 1896677 is a prime.

It is a super-2 number, since 2×1897189² = 7198652203442, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1897139) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 135507 + ... + 135520.

It is an arithmetic number, because the mean of its divisors is an integer number (542056).

2^1897189 is an apocalyptic number.

It is an amenable number.

1897189 is a deficient number, since it is larger than the sum of its proper divisors (271035).

1897189 is an equidigital number, since it uses as much as digits as its factorization.

1897189 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 271034.

The product of its digits is 36288, while the sum is 43.

The square root of 1897189 is about 1377.3848409214. The cubic root of 1897189 is about 123.7951221367.

The spelling of 1897189 in words is "one million, eight hundred ninety-seven thousand, one hundred eighty-nine".