66016261 has 2 divisors, whose sum is σ = 66016262. Its totient is φ = 66016260.

The previous prime is 66016207. The next prime is 66016283. The reversal of 66016261 is 16261066.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 58232161 + 7784100 = 7631^2 + 2790^2 .

It is a cyclic number.

It is not a de Polignac number, because 66016261 - 2¹⁵ = 65983493 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66016861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33008130 + 33008131.

It is an arithmetic number, because the mean of its divisors is an integer number (33008131).

Almost surely, 2^66016261 is an apocalyptic number.

It is an amenable number.

66016261 is a deficient number, since it is larger than the sum of its proper divisors (1).

66016261 is an equidigital number, since it uses as much as digits as its factorization.

66016261 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 66016261 is about 8125.0391383673. The cubic root of 66016261 is about 404.1571885308.

The spelling of 66016261 in words is "sixty-six million, sixteen thousand, two hundred sixty-one".