66278423 has 2 divisors, whose sum is σ = 66278424. Its totient is φ = 66278422.

The previous prime is 66278419. The next prime is 66278453. The reversal of 66278423 is 32487266.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66278423 - 2² = 66278419 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66278453) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33139211 + 33139212.

It is an arithmetic number, because the mean of its divisors is an integer number (33139212).

Almost surely, 2^66278423 is an apocalyptic number.

66278423 is a deficient number, since it is larger than the sum of its proper divisors (1).

66278423 is an equidigital number, since it uses as much as digits as its factorization.

66278423 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 96768, while the sum is 38.

The square root of 66278423 is about 8141.1561218294. The cubic root of 66278423 is about 404.6914746249.

The spelling of 66278423 in words is "sixty-six million, two hundred seventy-eight thousand, four hundred twenty-three".