39781966 has 16 divisors (see below), whose sum is σ = 69784704. Its totient is φ = 16652664.

The previous prime is 39781933. The next prime is 39781967. The reversal of 39781966 is 66918793.

39781966 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39781967) by changing a digit.

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 in 7 ways as a sum of consecutive naturals, for example, 32440 + ... + 33643.

It is an arithmetic number, because the mean of its divisors is an integer number (4361544).

Almost surely, 2^39781966 is an apocalyptic number.

39781966 is a deficient number, since it is larger than the sum of its proper divisors (30002738).

39781966 is a wasteful number, since it uses less digits than its factorization.

39781966 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66135.

The product of its digits is 489888, while the sum is 49.

The square root of 39781966 is about 6307.2946657026. The cubic root of 39781966 is about 341.3726687134.

The spelling of 39781966 in words is "thirty-nine million, seven hundred eighty-one thousand, nine hundred sixty-six".