66785010671 has 4 divisors (see below), whose sum is σ = 67021000392. Its totient is φ = 66549020952.

The previous prime is 66785010661. The next prime is 66785010709. The reversal of 66785010671 is 17601058766.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66785010671 is a prime.

It is a super-4 number, since 4×66785010671⁴ (a number of 44 digits) contains 4444 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66785010641) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 117994436 + ... + 117995001.

It is an arithmetic number, because the mean of its divisors is an integer number (16755250098).

Almost surely, 2^66785010671 is an apocalyptic number.

66785010671 is a deficient number, since it is larger than the sum of its proper divisors (235989721).

66785010671 is a wasteful number, since it uses less digits than its factorization.

66785010671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 235989720.

The product of its (nonzero) digits is 423360, while the sum is 47.

The spelling of 66785010671 in words is "sixty-six billion, seven hundred eighty-five million, ten thousand, six hundred seventy-one".