66880841 has 2 divisors, whose sum is σ = 66880842. Its totient is φ = 66880840.

The previous prime is 66880811. The next prime is 66880843. The reversal of 66880841 is 14808866.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 66765241 + 115600 = 8171^2 + 340^2 .

It is a cyclic number.

It is not a de Polignac number, because 66880841 - 2²² = 62686537 is a prime.

Together with 66880843, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (66880843) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33440420 + 33440421.

It is an arithmetic number, because the mean of its divisors is an integer number (33440421).

Almost surely, 2^66880841 is an apocalyptic number.

It is an amenable number.

66880841 is a deficient number, since it is larger than the sum of its proper divisors (1).

66880841 is an equidigital number, since it uses as much as digits as its factorization.

66880841 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 73728, while the sum is 41.

The square root of 66880841 is about 8178.0707382610. The cubic root of 66880841 is about 405.9138860613.

The spelling of 66880841 in words is "sixty-six million, eight hundred eighty thousand, eight hundred forty-one".