198915056639 has 16 divisors (see below), whose sum is σ = 217322988960. Its totient is φ = 180966666240.

The previous prime is 198915056621. The next prime is 198915056653. The reversal of 198915056639 is 936650519891.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 198915056639 - 2²⁰ = 198914008063 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198915056699) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23369 + ... + 631170.

It is an arithmetic number, because the mean of its divisors is an integer number (13582686810).

Almost surely, 2^198915056639 is an apocalyptic number.

198915056639 is a deficient number, since it is larger than the sum of its proper divisors (18407932321).

198915056639 is a wasteful number, since it uses less digits than its factorization.

198915056639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 654890.

The product of its (nonzero) digits is 15746400, while the sum is 62.

The spelling of 198915056639 in words is "one hundred ninety-eight billion, nine hundred fifteen million, fifty-six thousand, six hundred thirty-nine".