42891986 has 32 divisors (see below), whose sum is σ = 72258480. Its totient is φ = 18995200.

The previous prime is 42891943. The next prime is 42892001. The reversal of 42891986 is 68919824.

It can be written as a sum of positive squares in 8 ways, for example, as 19669225 + 23222761 = 4435^2 + 4819^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 42891986.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 39896 + ... + 40956.

Almost surely, 2^42891986 is an apocalyptic number.

42891986 is a deficient number, since it is larger than the sum of its proper divisors (29366494).

42891986 is a wasteful number, since it uses less digits than its factorization.

42891986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1150.

The product of its digits is 248832, while the sum is 47.

The square root of 42891986 is about 6549.1973554017. The cubic root of 42891986 is about 350.0462143057.

The spelling of 42891986 in words is "forty-two million, eight hundred ninety-one thousand, nine hundred eighty-six".