66077221 has 4 divisors (see below), whose sum is σ = 75516832. Its totient is φ = 56637612.

The previous prime is 66077189. The next prime is 66077233. The reversal of 66077221 is 12277066.

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 66077221 - 2⁵ = 66077189 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66077251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4719795 + ... + 4719808.

It is an arithmetic number, because the mean of its divisors is an integer number (18879208).

Almost surely, 2^66077221 is an apocalyptic number.

It is an amenable number.

66077221 is a deficient number, since it is larger than the sum of its proper divisors (9439611).

66077221 is an equidigital number, since it uses as much as digits as its factorization.

66077221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9439610.

The product of its (nonzero) digits is 7056, while the sum is 31.

The square root of 66077221 is about 8128.7896393006. The cubic root of 66077221 is about 404.2815510351.

The spelling of 66077221 in words is "sixty-six million, seventy-seven thousand, two hundred twenty-one".