1688999998 has 8 divisors (see below), whose sum is σ = 2895428592. Its totient is φ = 723857136.

The previous prime is 1688999953. The next prime is 1688999999. The reversal of 1688999998 is 8999998861.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1688999999) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 60321415 + ... + 60321442.

It is an arithmetic number, because the mean of its divisors is an integer number (361928574).

Almost surely, 2^1688999998 is an apocalyptic number.

1688999998 is a deficient number, since it is larger than the sum of its proper divisors (1206428594).

1688999998 is a wasteful number, since it uses less digits than its factorization.

1688999998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120642866.

The product of its digits is 181398528, while the sum is 76.

The square root of 1688999998 is about 41097.4451517366. The cubic root of 1688999998 is about 1190.9034398268.

The spelling of 1688999998 in words is "one billion, six hundred eighty-eight million, nine hundred ninety-nine thousand, nine hundred ninety-eight".