66243739 has 2 divisors, whose sum is σ = 66243740. Its totient is φ = 66243738.

The previous prime is 66243733. The next prime is 66243763. The reversal of 66243739 is 93734266.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66243739 - 2⁵ = 66243707 is a prime.

It is not a weakly prime, because it can be changed into another prime (66243733) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33121869 + 33121870.

It is an arithmetic number, because the mean of its divisors is an integer number (33121870).

Almost surely, 2^66243739 is an apocalyptic number.

66243739 is a deficient number, since it is larger than the sum of its proper divisors (1).

66243739 is an equidigital number, since it uses as much as digits as its factorization.

66243739 is an evil number, because the sum of its binary digits is even.

The product of its digits is 163296, while the sum is 40.

The square root of 66243739 is about 8139.0256787898. The cubic root of 66243739 is about 404.6208696044.

The spelling of 66243739 in words is "sixty-six million, two hundred forty-three thousand, seven hundred thirty-nine".