199438647 has 4 divisors (see below), whose sum is σ = 265918200. Its totient is φ = 132959096.

The previous prime is 199438643. The next prime is 199438661. The reversal of 199438647 is 746834991.

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 199438647 - 2² = 199438643 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 199438647.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (199438643) 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, 33239772 + ... + 33239777.

It is an arithmetic number, because the mean of its divisors is an integer number (66479550).

Almost surely, 2^199438647 is an apocalyptic number.

199438647 is a deficient number, since it is larger than the sum of its proper divisors (66479553).

199438647 is an equidigital number, since it uses as much as digits as its factorization.

199438647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66479552.

The product of its digits is 1306368, while the sum is 51.

The square root of 199438647 is about 14122.2748521617. The cubic root of 199438647 is about 584.2558995729.

The spelling of 199438647 in words is "one hundred ninety-nine million, four hundred thirty-eight thousand, six hundred forty-seven".