199168621 has 4 divisors (see below), whose sum is σ = 209651200. Its totient is φ = 188686044.

The previous prime is 199168591. The next prime is 199168643. The reversal of 199168621 is 126861991.

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, and also an emirpimes, since its reverse is a distinct semiprime: 126861991 = 367 ⋅345673.

It is a cyclic number.

It is not a de Polignac number, because 199168621 - 2⁵ = 199168589 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 (199168681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5241261 + ... + 5241298.

It is an arithmetic number, because the mean of its divisors is an integer number (52412800).

Almost surely, 2^199168621 is an apocalyptic number.

It is an amenable number.

199168621 is a deficient number, since it is larger than the sum of its proper divisors (10482579).

199168621 is a wasteful number, since it uses less digits than its factorization.

199168621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10482578.

The product of its digits is 46656, while the sum is 43.

The square root of 199168621 is about 14112.7113270271. The cubic root of 199168621 is about 583.9920999197.

The spelling of 199168621 in words is "one hundred ninety-nine million, one hundred sixty-eight thousand, six hundred twenty-one".