66222061 has 2 divisors, whose sum is σ = 66222062. Its totient is φ = 66222060.

The previous prime is 66222059. The next prime is 66222073. The reversal of 66222061 is 16022266.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 66113161 + 108900 = 8131^2 + 330^2 .

It is a cyclic number.

It is not a de Polignac number, because 66222061 - 2¹ = 66222059 is a prime.

It is a super-2 number, since 2×66222061² = 8770722726175442, which contains 22 as substring.

Together with 66222059, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66228061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33111030 + 33111031.

It is an arithmetic number, because the mean of its divisors is an integer number (33111031).

Almost surely, 2^66222061 is an apocalyptic number.

It is an amenable number.

66222061 is a deficient number, since it is larger than the sum of its proper divisors (1).

66222061 is an equidigital number, since it uses as much as digits as its factorization.

66222061 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 66222061 is about 8137.6938379371. The cubic root of 66222061 is about 404.5767279324.

The spelling of 66222061 in words is "sixty-six million, two hundred twenty-two thousand, sixty-one".