1806091998 has 16 divisors (see below), whose sum is σ = 3612691200. Its totient is φ = 601946136.

The previous prime is 1806091993. The next prime is 1806092033. The reversal of 1806091998 is 8991906081.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 1806091998.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1806091993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 37803 + ... + 71001.

It is an arithmetic number, because the mean of its divisors is an integer number (225793200).

Almost surely, 2^1806091998 is an apocalyptic number.

1806091998 is an abundant number, since it is smaller than the sum of its proper divisors (1806599202).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1806091998 is a wasteful number, since it uses less digits than its factorization.

1806091998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42271.

The product of its (nonzero) digits is 279936, while the sum is 51.

The square root of 1806091998 is about 42498.1411122887. The cubic root of 1806091998 is about 1217.8111783673.

The spelling of 1806091998 in words is "one billion, eight hundred six million, ninety-one thousand, nine hundred ninety-eight".