199231591 has 4 divisors (see below), whose sum is σ = 214557112. Its totient is φ = 183906072.

The previous prime is 199231579. The next prime is 199231633. The reversal of 199231591 is 195132991.

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 199231591 - 2⁵ = 199231559 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (199231541) 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, 7662741 + ... + 7662766.

It is an arithmetic number, because the mean of its divisors is an integer number (53639278).

Almost surely, 2^199231591 is an apocalyptic number.

199231591 is a deficient number, since it is larger than the sum of its proper divisors (15325521).

199231591 is a wasteful number, since it uses less digits than its factorization.

199231591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15325520.

The product of its digits is 21870, while the sum is 40.

The square root of 199231591 is about 14114.9421181952. The cubic root of 199231591 is about 584.0536392450.

The spelling of 199231591 in words is "one hundred ninety-nine million, two hundred thirty-one thousand, five hundred ninety-one".