66290281 has 2 divisors, whose sum is σ = 66290282. Its totient is φ = 66290280.

The previous prime is 66290197. The next prime is 66290299. The reversal of 66290281 is 18209266.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 66275881 + 14400 = 8141^2 + 120^2 .

It is a cyclic number.

It is not a de Polignac number, because 66290281 - 2²⁵ = 32735849 is a prime.

It is a super-2 number, since 2×66290281² = 8788802710117922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (66290381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33145140 + 33145141.

It is an arithmetic number, because the mean of its divisors is an integer number (33145141).

Almost surely, 2^66290281 is an apocalyptic number.

It is an amenable number.

66290281 is a deficient number, since it is larger than the sum of its proper divisors (1).

66290281 is an equidigital number, since it uses as much as digits as its factorization.

66290281 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10368, while the sum is 34.

The square root of 66290281 is about 8141.8843641997. The cubic root of 66290281 is about 404.7156078955.

The spelling of 66290281 in words is "sixty-six million, two hundred ninety thousand, two hundred eighty-one".