1818943890 has 16 divisors (see below), whose sum is σ = 4365465408. Its totient is φ = 485051696.

The previous prime is 1818943871. The next prime is 1818943901. The reversal of 1818943890 is 983498181.

It is an alternating number because its digits alternate between odd and even.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30315702 + ... + 30315761.

It is an arithmetic number, because the mean of its divisors is an integer number (272841588).

Almost surely, 2^1818943890 is an apocalyptic number.

1818943890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1818943890 is an abundant number, since it is smaller than the sum of its proper divisors (2546521518).

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

1818943890 is a wasteful number, since it uses less digits than its factorization.

1818943890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60631473.

The product of its (nonzero) digits is 497664, while the sum is 51.

The square root of 1818943890 is about 42649.0784191171. The cubic root of 1818943890 is about 1220.6929437072.

The spelling of 1818943890 in words is "one billion, eight hundred eighteen million, nine hundred forty-three thousand, eight hundred ninety".