1999797618 has 96 divisors (see below), whose sum is σ = 5241096576. Its totient is φ = 496364544.

The previous prime is 1999797593. The next prime is 1999797619. The reversal of 1999797618 is 8167979991.

It is not an unprimeable number, because it can be changed into a prime (1999797619) 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 47 ways as a sum of consecutive naturals, for example, 112380 + ... + 128952.

It is an arithmetic number, because the mean of its divisors is an integer number (54594756).

Almost surely, 2^1999797618 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1999797618, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2620548288).

1999797618 is an abundant number, since it is smaller than the sum of its proper divisors (3241298958).

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

1999797618 is a wasteful number, since it uses less digits than its factorization.

1999797618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16628 (or 16615 counting only the distinct ones).

The product of its digits is 15431472, while the sum is 66.

The square root of 1999797618 is about 44719.0967932046. The cubic root of 1999797618 is about 1259.8785509043.

The spelling of 1999797618 in words is "one billion, nine hundred ninety-nine million, seven hundred ninety-seven thousand, six hundred eighteen".