66757739 has 6 divisors (see below), whose sum is σ = 69139980. Its totient is φ = 64454936.

The previous prime is 66757727. The next prime is 66757741. The reversal of 66757739 is 93775766.

It is a de Polignac number, because none of the positive numbers 2^k-66757739 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66757039) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 38849 + ... + 40530.

It is an arithmetic number, because the mean of its divisors is an integer number (11523330).

Almost surely, 2^66757739 is an apocalyptic number.

66757739 is a deficient number, since it is larger than the sum of its proper divisors (2382241).

66757739 is an equidigital number, since it uses as much as digits as its factorization.

66757739 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79437 (or 79408 counting only the distinct ones).

The product of its digits is 1666980, while the sum is 50.

The square root of 66757739 is about 8170.5409245655. The cubic root of 66757739 is about 405.6646891331.

The spelling of 66757739 in words is "sixty-six million, seven hundred fifty-seven thousand, seven hundred thirty-nine".