1918331 has 4 divisors (see below), whose sum is σ = 2031192. Its totient is φ = 1805472.

The previous prime is 1918327. The next prime is 1918351. The reversal of 1918331 is 1338191.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1338191 = 67 ⋅19973.

It is a cyclic number.

It is not a de Polignac number, because 1918331 - 2² = 1918327 is a prime.

It is a super-2 number, since 2×1918331² = 7359987651122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1918331.

It is not an unprimeable number, because it can be changed into a prime (1918351) 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, 56405 + ... + 56438.

It is an arithmetic number, because the mean of its divisors is an integer number (507798).

2^1918331 is an apocalyptic number.

1918331 is a deficient number, since it is larger than the sum of its proper divisors (112861).

1918331 is a wasteful number, since it uses less digits than its factorization.

1918331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112860.

The product of its digits is 648, while the sum is 26.

The square root of 1918331 is about 1385.0382666194. The cubic root of 1918331 is about 124.2532761100.

The spelling of 1918331 in words is "one million, nine hundred eighteen thousand, three hundred thirty-one".