1999489973 has 8 divisors (see below), whose sum is σ = 2156107800. Its totient is φ = 1843273728.

The previous prime is 1999489963. The next prime is 1999489991. The reversal of 1999489973 is 3799849991.

It can be written as a sum of positive squares in 4 ways, for example, as 27952369 + 1971537604 = 5287^2 + 44402^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 1999489973 - 2⁴ = 1999489957 is a prime.

It is a Duffinian number.

1999489973 is a modest number, since divided by 89973 gives 19994 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1999489963) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 90008 + ... + 110001.

It is an arithmetic number, because the mean of its divisors is an integer number (269513475).

Almost surely, 2^1999489973 is an apocalyptic number.

1999489973 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

1999489973 is a deficient number, since it is larger than the sum of its proper divisors (156617827).

1999489973 is a wasteful number, since it uses less digits than its factorization.

1999489973 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 200791.

The product of its digits is 39680928, while the sum is 68.

The square root of 1999489973 is about 44715.6569111983. The cubic root of 1999489973 is about 1259.8139418308.

The spelling of 1999489973 in words is "one billion, nine hundred ninety-nine million, four hundred eighty-nine thousand, nine hundred seventy-three".