66742638 has 8 divisors (see below), whose sum is σ = 133485288. Its totient is φ = 22247544.

The previous prime is 66742609. The next prime is 66742639. The reversal of 66742638 is 83624766.

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

66742638 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 66742638.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66742639) by changing a digit.

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, 5561881 + ... + 5561892.

It is an arithmetic number, because the mean of its divisors is an integer number (16685661).

Almost surely, 2^66742638 is an apocalyptic number.

66742638 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66742638 is a wasteful number, since it uses less digits than its factorization.

66742638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11123778.

The product of its digits is 290304, while the sum is 42.

The square root of 66742638 is about 8169.6167596773. The cubic root of 66742638 is about 405.6340988998.

The spelling of 66742638 in words is "sixty-six million, seven hundred forty-two thousand, six hundred thirty-eight".