1818973 has 4 divisors (see below), whose sum is σ = 1958908. Its totient is φ = 1679040.

The previous prime is 1818937. The next prime is 1818977. The reversal of 1818973 is 3798181.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 71289 + 1747684 = 267^2 + 1322^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1818973 is a prime.

It is a Duffinian number.

1818973 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1818977) 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, 69948 + ... + 69973.

It is an arithmetic number, because the mean of its divisors is an integer number (489727).

2^1818973 is an apocalyptic number.

1818973 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

1818973 is a deficient number, since it is larger than the sum of its proper divisors (139935).

1818973 is a wasteful number, since it uses less digits than its factorization.

1818973 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139934.

The product of its digits is 12096, while the sum is 37.

The square root of 1818973 is about 1348.6930710877. The cubic root of 1818973 is about 122.0699455578.

The spelling of 1818973 in words is "one million, eight hundred eighteen thousand, nine hundred seventy-three".