1999104989 has 6 divisors (see below), whose sum is σ = 2325489534. Its totient is φ = 1713518520.

The previous prime is 1999104889. The next prime is 1999104997. The reversal of 1999104989 is 9894019991.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 1455422500 + 543682489 = 38150^2 + 23317^2 .

It is not a de Polignac number, because 1999104989 - 2⁸ = 1999104733 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1999104889) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 20398982 + ... + 20399079.

It is an arithmetic number, because the mean of its divisors is an integer number (387581589).

Almost surely, 2^1999104989 is an apocalyptic number.

It is an amenable number.

1999104989 is a deficient number, since it is larger than the sum of its proper divisors (326384545).

1999104989 is an equidigital number, since it uses as much as digits as its factorization.

1999104989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40798075 (or 40798068 counting only the distinct ones).

The product of its (nonzero) digits is 1889568, while the sum is 59.

The square root of 1999104989 is about 44711.3519030682. The cubic root of 1999104989 is about 1259.7330813200.

The spelling of 1999104989 in words is "one billion, nine hundred ninety-nine million, one hundred four thousand, nine hundred eighty-nine".