861000199 has 2 divisors, whose sum is σ = 861000200. Its totient is φ = 861000198.

The previous prime is 861000197. The next prime is 861000221. The reversal of 861000199 is 991000168.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 861000199 - 2¹ = 861000197 is a prime.

Together with 861000197, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (861000197) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 430500099 + 430500100.

It is an arithmetic number, because the mean of its divisors is an integer number (430500100).

Almost surely, 2^861000199 is an apocalyptic number.

861000199 is a deficient number, since it is larger than the sum of its proper divisors (1).

861000199 is an equidigital number, since it uses as much as digits as its factorization.

861000199 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3888, while the sum is 34.

The square root of 861000199 is about 29342.8048931932. The cubic root of 861000199 is about 951.3370642837.

The spelling of 861000199 in words is "eight hundred sixty-one million, one hundred ninety-nine", and thus it is an aban number.