18660640198 has 16 divisors (see below), whose sum is σ = 28355453280. Its totient is φ = 9209339136.

The previous prime is 18660640169. The next prime is 18660640277. The reversal of 18660640198 is 89104606681.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 56578 + ... + 201301.

It is an arithmetic number, because the mean of its divisors is an integer number (1772215830).

Almost surely, 2^18660640198 is an apocalyptic number.

18660640198 is a deficient number, since it is larger than the sum of its proper divisors (9694813082).

18660640198 is a wasteful number, since it uses less digits than its factorization.

18660640198 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 258351.

The product of its (nonzero) digits is 497664, while the sum is 49.

The spelling of 18660640198 in words is "eighteen billion, six hundred sixty million, six hundred forty thousand, one hundred ninety-eight".