66486391 has 2 divisors, whose sum is σ = 66486392. Its totient is φ = 66486390.

The previous prime is 66486389. The next prime is 66486421. The reversal of 66486391 is 19368466.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66486391 - 2¹ = 66486389 is a prime.

Together with 66486389, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66486361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33243195 + 33243196.

It is an arithmetic number, because the mean of its divisors is an integer number (33243196).

Almost surely, 2^66486391 is an apocalyptic number.

66486391 is a deficient number, since it is larger than the sum of its proper divisors (1).

66486391 is an equidigital number, since it uses as much as digits as its factorization.

66486391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 186624, while the sum is 43.

The square root of 66486391 is about 8153.9187511282. The cubic root of 66486391 is about 405.1143120902.

The spelling of 66486391 in words is "sixty-six million, four hundred eighty-six thousand, three hundred ninety-one".