199723541 has 4 divisors (see below), whose sum is σ = 200758572. Its totient is φ = 198688512.

The previous prime is 199723529. The next prime is 199723567. The reversal of 199723541 is 145327991.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 145327991 = 101 ⋅1438891.

It can be written as a sum of positive squares in 2 ways, for example, as 121330225 + 78393316 = 11015^2 + 8854^2 .

It is a cyclic number.

It is not a de Polignac number, because 199723541 - 2¹⁸ = 199461397 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 (199723501) 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, 517226 + ... + 517611.

It is an arithmetic number, because the mean of its divisors is an integer number (50189643).

Almost surely, 2^199723541 is an apocalyptic number.

It is an amenable number.

199723541 is a deficient number, since it is larger than the sum of its proper divisors (1035031).

199723541 is a wasteful number, since it uses less digits than its factorization.

199723541 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1035030.

The product of its digits is 68040, while the sum is 41.

The square root of 199723541 is about 14132.3579419713. The cubic root of 199723541 is about 584.5339663842.

The spelling of 199723541 in words is "one hundred ninety-nine million, seven hundred twenty-three thousand, five hundred forty-one".