66856390379 has 8 divisors (see below), whose sum is σ = 67047552000. Its totient is φ = 66665406312.

The previous prime is 66856390373. The next prime is 66856390397. The reversal of 66856390379 is 97309365866.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66856390379 - 2²⁰ = 66855341803 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66856390373) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 728912 + ... + 815490.

It is an arithmetic number, because the mean of its divisors is an integer number (8380944000).

Almost surely, 2^66856390379 is an apocalyptic number.

66856390379 is a deficient number, since it is larger than the sum of its proper divisors (191161621).

66856390379 is a wasteful number, since it uses less digits than its factorization.

66856390379 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88777.

The product of its (nonzero) digits is 44089920, while the sum is 62.

The spelling of 66856390379 in words is "sixty-six billion, eight hundred fifty-six million, three hundred ninety thousand, three hundred seventy-nine".