1998438699 has 8 divisors (see below), whose sum is σ = 2665067472. Its totient is φ = 1332051200.

The previous prime is 1998438683. The next prime is 1998438703. The reversal of 1998438699 is 9968348991.

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 1998438699 - 2⁴ = 1998438683 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1998434699) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40014 + ... + 74819.

It is an arithmetic number, because the mean of its divisors is an integer number (333133434).

Almost surely, 2^1998438699 is an apocalyptic number.

1998438699 is a deficient number, since it is larger than the sum of its proper divisors (666628773).

1998438699 is a wasteful number, since it uses less digits than its factorization.

1998438699 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 120637.

The product of its digits is 30233088, while the sum is 66.

The square root of 1998438699 is about 44703.9002660842. The cubic root of 1998438699 is about 1259.5931118792.

The spelling of 1998438699 in words is "one billion, nine hundred ninety-eight million, four hundred thirty-eight thousand, six hundred ninety-nine".