199471521 has 4 divisors (see below), whose sum is σ = 265962032. Its totient is φ = 132981012.

The previous prime is 199471513. The next prime is 199471537. The reversal of 199471521 is 125174991.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 199471521 - 2³ = 199471513 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 199471521.

It is not an unprimeable number, because it can be changed into a prime (199471721) 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, 33245251 + ... + 33245256.

It is an arithmetic number, because the mean of its divisors is an integer number (66490508).

Almost surely, 2^199471521 is an apocalyptic number.

It is an amenable number.

199471521 is a deficient number, since it is larger than the sum of its proper divisors (66490511).

199471521 is an equidigital number, since it uses as much as digits as its factorization.

199471521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66490510.

The product of its digits is 22680, while the sum is 39.

The square root of 199471521 is about 14123.4387101725. The cubic root of 199471521 is about 584.2879992914.

The spelling of 199471521 in words is "one hundred ninety-nine million, four hundred seventy-one thousand, five hundred twenty-one".