72158186 has 4 divisors (see below), whose sum is σ = 108237282. Its totient is φ = 36079092.

The previous prime is 72158161. The next prime is 72158209. The reversal of 72158186 is 68185127.

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., 68475625 + 3682561 = 8275^2 + 1919^2 .

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18039545 + ... + 18039548.

Almost surely, 2^72158186 is an apocalyptic number.

72158186 is a deficient number, since it is larger than the sum of its proper divisors (36079096).

72158186 is a wasteful number, since it uses less digits than its factorization.

72158186 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36079095.

The product of its digits is 26880, while the sum is 38.

The square root of 72158186 is about 8494.5974595622. The cubic root of 72158186 is about 416.3212085578.

The spelling of 72158186 in words is "seventy-two million, one hundred fifty-eight thousand, one hundred eighty-six".