138946666 has 8 divisors (see below), whose sum is σ = 209330820. Its totient is φ = 69169728.

The previous prime is 138946651. The next prime is 138946673. The reversal of 138946666 is 666649831.

138946666 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 138415225 + 531441 = 11765^2 + 729^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 151231 + ... + 152146.

Almost surely, 2^138946666 is an apocalyptic number.

138946666 is a deficient number, since it is larger than the sum of its proper divisors (70384154).

138946666 is a wasteful number, since it uses less digits than its factorization.

138946666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 303608.

The product of its digits is 1119744, while the sum is 49.

The square root of 138946666 is about 11787.5640401230. The cubic root of 138946666 is about 517.9438851374.

The spelling of 138946666 in words is "one hundred thirty-eight million, nine hundred forty-six thousand, six hundred sixty-six".