66739994 has 8 divisors (see below), whose sum is σ = 105998868. Its totient is φ = 31407040.

The previous prime is 66739969. The next prime is 66740021. The reversal of 66739994 is 49993766.

It can be written as a sum of positive squares in 2 ways, for example, as 63409369 + 3330625 = 7963^2 + 1825^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 981437 + ... + 981504.

Almost surely, 2^66739994 is an apocalyptic number.

66739994 is a deficient number, since it is larger than the sum of its proper divisors (39258874).

66739994 is a wasteful number, since it uses less digits than its factorization.

66739994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1962960.

The product of its digits is 2204496, while the sum is 53.

The square root of 66739994 is about 8169.4549389785. The cubic root of 66739994 is about 405.6287424503.

The spelling of 66739994 in words is "sixty-six million, seven hundred thirty-nine thousand, nine hundred ninety-four".