66059993 has 4 divisors (see below), whose sum is σ = 66144720. Its totient is φ = 65975268.

The previous prime is 66059969. The next prime is 66060031. The reversal of 66059993 is 39995066.

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, and also an emirpimes, since its reverse is a distinct semiprime: 39995066 = 2 ⋅19997533.

It is a cyclic number.

It is not a de Polignac number, because 66059993 - 2⁸ = 66059737 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (66059293) 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, 41183 + ... + 42756.

It is an arithmetic number, because the mean of its divisors is an integer number (16536180).

Almost surely, 2^66059993 is an apocalyptic number.

It is an amenable number.

66059993 is a deficient number, since it is larger than the sum of its proper divisors (84727).

66059993 is an equidigital number, since it uses as much as digits as its factorization.

66059993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84726.

The product of its (nonzero) digits is 393660, while the sum is 47.

The square root of 66059993 is about 8127.7298798619. The cubic root of 66059993 is about 404.2464125116.

The spelling of 66059993 in words is "sixty-six million, fifty-nine thousand, nine hundred ninety-three".