66687593 has 4 divisors (see below), whose sum is σ = 76214400. Its totient is φ = 57160788.

The previous prime is 66687581. The next prime is 66687619. The reversal of 66687593 is 39578666.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 66687593 - 2⁶ = 66687529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66687553) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4763393 + ... + 4763406.

It is an arithmetic number, because the mean of its divisors is an integer number (19053600).

Almost surely, 2^66687593 is an apocalyptic number.

It is an amenable number.

66687593 is a deficient number, since it is larger than the sum of its proper divisors (9526807).

66687593 is an equidigital number, since it uses as much as digits as its factorization.

66687593 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9526806.

The product of its digits is 1632960, while the sum is 50.

The square root of 66687593 is about 8166.2471797026. The cubic root of 66687593 is about 405.5225546620.

The spelling of 66687593 in words is "sixty-six million, six hundred eighty-seven thousand, five hundred ninety-three".