66971438 has 8 divisors (see below), whose sum is σ = 100495080. Its totient is φ = 33473080.

The previous prime is 66971413. The next prime is 66971459. The reversal of 66971438 is 83417966.

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

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3128 + ... + 11988.

It is an arithmetic number, because the mean of its divisors is an integer number (12561885).

Almost surely, 2^66971438 is an apocalyptic number.

66971438 is a deficient number, since it is larger than the sum of its proper divisors (33523642).

66971438 is a wasteful number, since it uses less digits than its factorization.

66971438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12642.

The product of its digits is 217728, while the sum is 44.

The square root of 66971438 is about 8183.6078840570. The cubic root of 66971438 is about 406.0970874450.

The spelling of 66971438 in words is "sixty-six million, nine hundred seventy-one thousand, four hundred thirty-eight".