66081019 has 2 divisors, whose sum is σ = 66081020. Its totient is φ = 66081018.

The previous prime is 66081011. The next prime is 66081061. The reversal of 66081019 is 91018066.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66081019 - 2³ = 66081011 is a prime.

It is a super-2 number, since 2×66081019² = 8733402144156722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (66081011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33040509 + 33040510.

It is an arithmetic number, because the mean of its divisors is an integer number (33040510).

Almost surely, 2^66081019 is an apocalyptic number.

66081019 is a deficient number, since it is larger than the sum of its proper divisors (1).

66081019 is an equidigital number, since it uses as much as digits as its factorization.

66081019 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2592, while the sum is 31.

The square root of 66081019 is about 8129.0232500590. The cubic root of 66081019 is about 404.2892966792.

The spelling of 66081019 in words is "sixty-six million, eighty-one thousand, nineteen".