66681974 has 8 divisors (see below), whose sum is σ = 100059960. Its totient is φ = 33328656.

The previous prime is 66681959. The next prime is 66681983. The reversal of 66681974 is 47918666.

It is a happy number.

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

It is a congruent number.

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, 3842 + ... + 12170.

It is an arithmetic number, because the mean of its divisors is an integer number (12507495).

Almost surely, 2^66681974 is an apocalyptic number.

66681974 is a deficient number, since it is larger than the sum of its proper divisors (33377986).

66681974 is a wasteful number, since it uses less digits than its factorization.

66681974 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12334.

The product of its digits is 435456, while the sum is 47.

The square root of 66681974 is about 8165.9031343753. The cubic root of 66681974 is about 405.5111647611.

The spelling of 66681974 in words is "sixty-six million, six hundred eighty-one thousand, nine hundred seventy-four".