199557081108 has 252 divisors, whose sum is σ = 664459602912. Its totient is φ = 51832599840.

The previous prime is 199557081091. The next prime is 199557081109. The reversal of 199557081108 is 801180755991.

It is a happy number.

199557081108 is a `hidden beast` number, since 1 + 9 + 9 + 557 + 0 + 81 + 1 + 0 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (252).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (199557081109) by changing a digit.

It is a polite number, since it can be written in 83 ways as a sum of consecutive naturals, for example, 1508241 + ... + 1635207.

It is an arithmetic number, because the mean of its divisors is an integer number (2636744456).

Almost surely, 2^199557081108 is an apocalyptic number.

199557081108 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 199557081108, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (332229801456).

199557081108 is an abundant number, since it is smaller than the sum of its proper divisors (464902521804).

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

199557081108 is a wasteful number, since it uses less digits than its factorization.

199557081108 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 127014 (or 126990 counting only the distinct ones).

The product of its (nonzero) digits is 907200, while the sum is 54.

The spelling of 199557081108 in words is "one hundred ninety-nine billion, five hundred fifty-seven million, eighty-one thousand, one hundred eight".