66422261 has 4 divisors (see below), whose sum is σ = 66513612. Its totient is φ = 66330912.

The previous prime is 66422249. The next prime is 66422269. The reversal of 66422261 is 16222466.

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

It can be written as a sum of positive squares in 2 ways, for example, as 65918161 + 504100 = 8119^2 + 710^2 .

It is a cyclic number.

It is not a de Polignac number, because 66422261 - 2¹⁰ = 66421237 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 (66422269) 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, 44576 + ... + 46041.

It is an arithmetic number, because the mean of its divisors is an integer number (16628403).

Almost surely, 2^66422261 is an apocalyptic number.

It is an amenable number.

66422261 is a deficient number, since it is larger than the sum of its proper divisors (91351).

66422261 is an equidigital number, since it uses as much as digits as its factorization.

66422261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91350.

The product of its digits is 6912, while the sum is 29.

The square root of 66422261 is about 8149.9853374101. The cubic root of 66422261 is about 404.9840180657.

The spelling of 66422261 in words is "sixty-six million, four hundred twenty-two thousand, two hundred sixty-one".