199643231 has 4 divisors (see below), whose sum is σ = 205039032. Its totient is φ = 194247432.

The previous prime is 199643219. The next prime is 199643321. The reversal of 199643231 is 132346991.

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 199643231 - 2⁶ = 199643167 is a prime.

It is a super-2 number, since 2×199643231² = 79714839368238722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (199645231) 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, 2697845 + ... + 2697918.

It is an arithmetic number, because the mean of its divisors is an integer number (51259758).

Almost surely, 2^199643231 is an apocalyptic number.

199643231 is a deficient number, since it is larger than the sum of its proper divisors (5395801).

199643231 is an equidigital number, since it uses as much as digits as its factorization.

199643231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5395800.

The product of its digits is 34992, while the sum is 38.

The square root of 199643231 is about 14129.5163045307. The cubic root of 199643231 is about 584.4556077087.

The spelling of 199643231 in words is "one hundred ninety-nine million, six hundred forty-three thousand, two hundred thirty-one".