1981941018 has 8 divisors (see below), whose sum is σ = 3963882048. Its totient is φ = 660647004.

The previous prime is 1981941007. The next prime is 1981941083. The reversal of 1981941018 is 8101491891.

It is a happy number.

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

1981941018 is an admirable number.

It is a Curzon 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, 165161746 + ... + 165161757.

It is an arithmetic number, because the mean of its divisors is an integer number (495485256).

Almost surely, 2^1981941018 is an apocalyptic number.

1981941018 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

1981941018 is a wasteful number, since it uses less digits than its factorization.

1981941018 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 330323508.

The product of its (nonzero) digits is 20736, while the sum is 42.

The square root of 1981941018 is about 44518.9961477120. The cubic root of 1981941018 is about 1256.1174299749.

The spelling of 1981941018 in words is "one billion, nine hundred eighty-one million, nine hundred forty-one thousand, eighteen".