199466569891 has 4 divisors (see below), whose sum is σ = 199491740752. Its totient is φ = 199441399032.

The previous prime is 199466569889. The next prime is 199466569919. The reversal of 199466569891 is 198965664991.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 199466569891 - 2¹ = 199466569889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (199466561891) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12573540 + ... + 12589393.

It is an arithmetic number, because the mean of its divisors is an integer number (49872935188).

Almost surely, 2^199466569891 is an apocalyptic number.

199466569891 is a deficient number, since it is larger than the sum of its proper divisors (25170861).

199466569891 is an equidigital number, since it uses as much as digits as its factorization.

199466569891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25170860.

The product of its digits is 226748160, while the sum is 73.

The spelling of 199466569891 in words is "one hundred ninety-nine billion, four hundred sixty-six million, five hundred sixty-nine thousand, eight hundred ninety-one".