199919101 has 2 divisors, whose sum is σ = 199919102. Its totient is φ = 199919100.

The previous prime is 199919077. The next prime is 199919107. The reversal of 199919101 is 101919991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 189200025 + 10719076 = 13755^2 + 3274^2 .

It is an emirp because it is prime and its reverse (101919991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 199919101 - 2¹⁵ = 199886333 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199919107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99959550 + 99959551.

It is an arithmetic number, because the mean of its divisors is an integer number (99959551).

Almost surely, 2^199919101 is an apocalyptic number.

It is an amenable number.

199919101 is a deficient number, since it is larger than the sum of its proper divisors (1).

199919101 is an equidigital number, since it uses as much as digits as its factorization.

199919101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6561, while the sum is 40.

The square root of 199919101 is about 14139.2751228626. The cubic root of 199919101 is about 584.7246869717.

It can be divided in two parts, 19991 and 9101, that added together give a palindrome (29092).

The spelling of 199919101 in words is "one hundred ninety-nine million, nine hundred nineteen thousand, one hundred one".