199999531 has 4 divisors (see below), whose sum is σ = 201035992. Its totient is φ = 198963072.

The previous prime is 199999483. The next prime is 199999589. The reversal of 199999531 is 135999991.

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 199999531 - 2¹³ = 199991339 is a prime.

It is a super-2 number, since 2×199999531² = 79999624800439922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (199999231) 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, 517941 + ... + 518326.

It is an arithmetic number, because the mean of its divisors is an integer number (50258998).

Almost surely, 2^199999531 is an apocalyptic number.

199999531 is a deficient number, since it is larger than the sum of its proper divisors (1036461).

199999531 is a wasteful number, since it uses less digits than its factorization.

199999531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1036460.

The product of its digits is 885735, while the sum is 55.

The square root of 199999531 is about 14142.1190420672. The cubic root of 199999531 is about 584.8030905208.

The spelling of 199999531 in words is "one hundred ninety-nine million, nine hundred ninety-nine thousand, five hundred thirty-one".