1638071019198 has 48 divisors (see below), whose sum is σ = 3557036710656. Its totient is φ = 544811857920.

The previous prime is 1638071019197. The next prime is 1638071019227. The reversal of 1638071019198 is 8919101708361.

1638071019198 is a `hidden beast` number, since 1 + 6 + 380 + 71 + 0 + 1 + 9 + 198 = 666.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1638071019197) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 21887490 + ... + 21962202.

It is an arithmetic number, because the mean of its divisors is an integer number (74104931472).

Almost surely, 2^{1638071019198} is an apocalyptic number.

1638071019198 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

1638071019198 is an abundant number, since it is smaller than the sum of its proper divisors (1918965691458).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1638071019198 is a wasteful number, since it uses less digits than its factorization.

1638071019198 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77409 (or 77406 counting only the distinct ones).

The product of its (nonzero) digits is 653184, while the sum is 54.

The spelling of 1638071019198 in words is "one trillion, six hundred thirty-eight billion, seventy-one million, nineteen thousand, one hundred ninety-eight".