198868581 has 16 divisors (see below), whose sum is σ = 298173120. Its totient is φ = 130980240.

The previous prime is 198868547. The next prime is 198868591. The reversal of 198868581 is 185868891.

It is not a de Polignac number, because 198868581 - 2¹⁷ = 198737509 is a prime.

It is a super-2 number, since 2×198868581² = 79097425017907122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198868531) 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, 42130 + ... + 46611.

It is an arithmetic number, because the mean of its divisors is an integer number (18635820).

Almost surely, 2^198868581 is an apocalyptic number.

It is an amenable number.

198868581 is a deficient number, since it is larger than the sum of its proper divisors (99304539).

198868581 is an equidigital number, since it uses as much as digits as its factorization.

198868581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88833 (or 88827 counting only the distinct ones).

The product of its digits is 1105920, while the sum is 54.

The square root of 198868581 is about 14102.0771874217. The cubic root of 198868581 is about 583.6986985288.

The spelling of 198868581 in words is "one hundred ninety-eight million, eight hundred sixty-eight thousand, five hundred eighty-one".