199934621 has 4 divisors (see below), whose sum is σ = 199962972. Its totient is φ = 199906272.

The previous prime is 199934599. The next prime is 199934641. The reversal of 199934621 is 126439991.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 126439991 = 173 ⋅730867.

It can be written as a sum of positive squares in 2 ways, for example, as 160934596 + 39000025 = 12686^2 + 6245^2 .

It is a cyclic number.

It is not a de Polignac number, because 199934621 - 2¹⁰ = 199933597 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (199934641) 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, 5591 + ... + 20763.

It is an arithmetic number, because the mean of its divisors is an integer number (49990743).

Almost surely, 2^199934621 is an apocalyptic number.

It is an amenable number.

199934621 is a deficient number, since it is larger than the sum of its proper divisors (28351).

199934621 is a wasteful number, since it uses less digits than its factorization.

199934621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28350.

The product of its digits is 104976, while the sum is 44.

The square root of 199934621 is about 14139.8239380835. The cubic root of 199934621 is about 584.7398175792.

The spelling of 199934621 in words is "one hundred ninety-nine million, nine hundred thirty-four thousand, six hundred twenty-one".