866871397 has 6 divisors (see below), whose sum is σ = 1008401478. Its totient is φ = 743032584.

The previous prime is 866871389. The next prime is 866871419. The reversal of 866871397 is 793178668.

It can be written as a sum of positive squares in only one way, i.e., 476374276 + 390497121 = 21826^2 + 19761^2 .

It is not a de Polignac number, because 866871397 - 2³ = 866871389 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (866871367) 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, 8845578 + ... + 8845675.

It is an arithmetic number, because the mean of its divisors is an integer number (168066913).

Almost surely, 2^866871397 is an apocalyptic number.

It is an amenable number.

866871397 is a deficient number, since it is larger than the sum of its proper divisors (141530081).

866871397 is a wasteful number, since it uses less digits than its factorization.

866871397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17691267 (or 17691260 counting only the distinct ones).

The product of its digits is 3048192, while the sum is 55.

The square root of 866871397 is about 29442.6798542524. The cubic root of 866871397 is about 953.4945706576.

The spelling of 866871397 in words is "eight hundred sixty-six million, eight hundred seventy-one thousand, three hundred ninety-seven".