1800440990 has 8 divisors (see below), whose sum is σ = 3240793800. Its totient is φ = 720176392.

The previous prime is 1800440923. The next prime is 1800441011. The reversal of 1800440990 is 990440081.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1800440990.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 90022040 + ... + 90022059.

It is an arithmetic number, because the mean of its divisors is an integer number (405099225).

Almost surely, 2^1800440990 is an apocalyptic number.

1800440990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1800440990 is a deficient number, since it is larger than the sum of its proper divisors (1440352810).

1800440990 is a wasteful number, since it uses less digits than its factorization.

1800440990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 180044106.

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 1800440990 is about 42431.6036699062. The cubic root of 1800440990 is about 1216.5397313831.

The spelling of 1800440990 in words is "one billion, eight hundred million, four hundred forty thousand, nine hundred ninety".