80666491 has 2 divisors, whose sum is σ = 80666492. Its totient is φ = 80666490.

The previous prime is 80666489. The next prime is 80666507. The reversal of 80666491 is 19466608.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 80666491 - 2¹ = 80666489 is a prime.

Together with 80666489, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (80666291) 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, 40333245 + 40333246.

It is an arithmetic number, because the mean of its divisors is an integer number (40333246).

Almost surely, 2^80666491 is an apocalyptic number.

80666491 is a deficient number, since it is larger than the sum of its proper divisors (1).

80666491 is an equidigital number, since it uses as much as digits as its factorization.

80666491 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 62208, while the sum is 40.

The square root of 80666491 is about 8981.4526107974. The cubic root of 80666491 is about 432.0802230845.

The spelling of 80666491 in words is "eighty million, six hundred sixty-six thousand, four hundred ninety-one".