42781866 has 16 divisors (see below), whose sum is σ = 85791744. Its totient is φ = 14222624.

The previous prime is 42781859. The next prime is 42781889. The reversal of 42781866 is 66818724.

It is a Smith number, since the sum of its digits (42) 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 a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7011 + ... + 11606.

It is an arithmetic number, because the mean of its divisors is an integer number (5361984).

Almost surely, 2^42781866 is an apocalyptic number.

42781866 is an abundant number, since it is smaller than the sum of its proper divisors (43009878).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

42781866 is a wasteful number, since it uses less digits than its factorization.

42781866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19005.

The product of its digits is 129024, while the sum is 42.

The square root of 42781866 is about 6540.7848152955. The cubic root of 42781866 is about 349.7463904289.

The spelling of 42781866 in words is "forty-two million, seven hundred eighty-one thousand, eight hundred sixty-six".