42991186 has 32 divisors (see below), whose sum is σ = 80962560. Its totient is φ = 16693776.

The previous prime is 42991177. The next prime is 42991213. The reversal of 42991186 is 68119924.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is an upside-down number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2605 + ... + 9631.

It is an arithmetic number, because the mean of its divisors is an integer number (2530080).

Almost surely, 2^42991186 is an apocalyptic number.

42991186 is a gapful number since it is divisible by the number (46) formed by its first and last digit.

42991186 is a deficient number, since it is larger than the sum of its proper divisors (37971374).

42991186 is a wasteful number, since it uses less digits than its factorization.

42991186 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7078.

The product of its digits is 31104, while the sum is 40.

The square root of 42991186 is about 6556.7664286598. The cubic root of 42991186 is about 350.3158672320.

The spelling of 42991186 in words is "forty-two million, nine hundred ninety-one thousand, one hundred eighty-six".