866957394999 has 4 divisors (see below), whose sum is σ = 1155943193336. Its totient is φ = 577971596664.

The previous prime is 866957394983. The next prime is 866957395013. The reversal of 866957394999 is 999493759668.

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

It is not a de Polignac number, because 866957394999 - 2⁴ = 866957394983 is a prime.

It is a super-2 number, since 2×866957394999² (a number of 25 digits) contains 22 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 (866957398999) 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, 144492899164 + ... + 144492899169.

It is an arithmetic number, because the mean of its divisors is an integer number (288985798334).

Almost surely, 2^866957394999 is an apocalyptic number.

866957394999 is a deficient number, since it is larger than the sum of its proper divisors (288985798337).

866957394999 is a wasteful number, since it uses less digits than its factorization.

866957394999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 288985798336.

The product of its digits is 7142567040, while the sum is 84.

The spelling of 866957394999 in words is "eight hundred sixty-six billion, nine hundred fifty-seven million, three hundred ninety-four thousand, nine hundred ninety-nine".