2158186 has 4 divisors (see below), whose sum is σ = 3237282. Its totient is φ = 1079092.

The previous prime is 2158183. The next prime is 2158223. The reversal of 2158186 is 6818512.

2158186 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 2157961 + 225 = 1469^2 + 15^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (2158181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 539545 + ... + 539548.

2^2158186 is an apocalyptic number.

2158186 is a deficient number, since it is larger than the sum of its proper divisors (1079096).

2158186 is a wasteful number, since it uses less digits than its factorization.

2158186 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1079095.

The product of its digits is 3840, while the sum is 31.

The square root of 2158186 is about 1469.0765807132. The cubic root of 2158186 is about 129.2298847438.

The spelling of 2158186 in words is "two million, one hundred fifty-eight thousand, one hundred eighty-six".