191816 has 8 divisors (see below), whose sum is σ = 359670. Its totient is φ = 95904.

The previous prime is 191803. The next prime is 191827. The reversal of 191816 is 618191.

191816 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 168100 + 23716 = 410^2 + 154^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11981 + ... + 11996.

2¹⁹¹⁸¹⁶ is an apocalyptic number.

It is an amenable number.

191816 is a deficient number, since it is larger than the sum of its proper divisors (167854).

191816 is a wasteful number, since it uses less digits than its factorization.

191816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23983 (or 23979 counting only the distinct ones).

The product of its digits is 432, while the sum is 26.

The square root of 191816 is about 437.9680353633. The cubic root of 191816 is about 57.6715481777.

The spelling of 191816 in words is "one hundred ninety-one thousand, eight hundred sixteen".