199861901 has 8 divisors (see below), whose sum is σ = 205511904. Its totient is φ = 194225040.

The previous prime is 199861897. The next prime is 199861919. The reversal of 199861901 is 109168991.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 199861901 - 2² = 199861897 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 (199861951) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33146 + ... + 38708.

It is an arithmetic number, because the mean of its divisors is an integer number (25688988).

Almost surely, 2^199861901 is an apocalyptic number.

It is an amenable number.

199861901 is a deficient number, since it is larger than the sum of its proper divisors (5650003).

199861901 is an equidigital number, since it uses as much as digits as its factorization.

199861901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6571.

The product of its (nonzero) digits is 34992, while the sum is 44.

The square root of 199861901 is about 14137.2522436292. The cubic root of 199861901 is about 584.6689153416.

The spelling of 199861901 in words is "one hundred ninety-nine million, eight hundred sixty-one thousand, nine hundred one".