66642259 has 2 divisors, whose sum is σ = 66642260. Its totient is φ = 66642258.

The previous prime is 66642197. The next prime is 66642263. The reversal of 66642259 is 95224666.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66642259 - 2¹⁹ = 66117971 is a prime.

It is not a weakly prime, because it can be changed into another prime (66642559) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33321129 + 33321130.

It is an arithmetic number, because the mean of its divisors is an integer number (33321130).

Almost surely, 2^66642259 is an apocalyptic number.

66642259 is a deficient number, since it is larger than the sum of its proper divisors (1).

66642259 is an equidigital number, since it uses as much as digits as its factorization.

66642259 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 155520, while the sum is 40.

The square root of 66642259 is about 8163.4710142194. The cubic root of 66642259 is about 405.4306428784.

The spelling of 66642259 in words is "sixty-six million, six hundred forty-two thousand, two hundred fifty-nine".