66720227 has 4 divisors (see below), whose sum is σ = 76251696. Its totient is φ = 57188760.

The previous prime is 66720211. The next prime is 66720289. The reversal of 66720227 is 72202766.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66720227 - 2⁴ = 66720211 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 66720193 and 66720202.

It is not an unprimeable number, because it can be changed into a prime (66720727) 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, 4765724 + ... + 4765737.

It is an arithmetic number, because the mean of its divisors is an integer number (19062924).

Almost surely, 2^66720227 is an apocalyptic number.

66720227 is a deficient number, since it is larger than the sum of its proper divisors (9531469).

66720227 is an equidigital number, since it uses as much as digits as its factorization.

66720227 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9531468.

The product of its (nonzero) digits is 14112, while the sum is 32.

The square root of 66720227 is about 8168.2450379503. The cubic root of 66720227 is about 405.5886922265.

The spelling of 66720227 in words is "sixty-six million, seven hundred twenty thousand, two hundred twenty-seven".