199835861 has 2 divisors, whose sum is σ = 199835862. Its totient is φ = 199835860.

The previous prime is 199835837. The next prime is 199835879. The reversal of 199835861 is 168538991.

It is a happy number.

199835861 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 199798225 + 37636 = 14135^2 + 194^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-199835861 is a prime.

It is a super-2 number, since 2×199835861² = 79868742683222642, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199835761) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99917930 + 99917931.

It is an arithmetic number, because the mean of its divisors is an integer number (99917931).

Almost surely, 2^199835861 is an apocalyptic number.

It is an amenable number.

199835861 is a deficient number, since it is larger than the sum of its proper divisors (1).

199835861 is an equidigital number, since it uses as much as digits as its factorization.

199835861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 466560, while the sum is 50.

The square root of 199835861 is about 14136.3312425820. The cubic root of 199835861 is about 584.6435220747.

The spelling of 199835861 in words is "one hundred ninety-nine million, eight hundred thirty-five thousand, eight hundred sixty-one".