66917685 has 16 divisors (see below), whose sum is σ = 110522880. Its totient is φ = 34537920.

The previous prime is 66917663. The next prime is 66917687. The reversal of 66917685 is 58671966.

It is not a de Polignac number, because 66917685 - 2¹¹ = 66915637 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66917687) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 71490 + ... + 72419.

It is an arithmetic number, because the mean of its divisors is an integer number (6907680).

Almost surely, 2^66917685 is an apocalyptic number.

It is an amenable number.

66917685 is a deficient number, since it is larger than the sum of its proper divisors (43605195).

66917685 is a wasteful number, since it uses less digits than its factorization.

66917685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143948.

The product of its digits is 544320, while the sum is 48.

The square root of 66917685 is about 8180.3230376312. The cubic root of 66917685 is about 405.9884103723.

The spelling of 66917685 in words is "sixty-six million, nine hundred seventeen thousand, six hundred eighty-five".