866195139 has 16 divisors (see below), whose sum is σ = 1183491584. Its totient is φ = 563220000.

The previous prime is 866195137. The next prime is 866195167. The reversal of 866195139 is 931591668.

It is not a de Polignac number, because 866195139 - 2¹ = 866195137 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (866195137) 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, 92409 + ... + 101349.

It is an arithmetic number, because the mean of its divisors is an integer number (73968224).

Almost surely, 2^866195139 is an apocalyptic number.

866195139 is a deficient number, since it is larger than the sum of its proper divisors (317296445).

866195139 is a wasteful number, since it uses less digits than its factorization.

866195139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9738.

The product of its digits is 349920, while the sum is 48.

The square root of 866195139 is about 29431.1932989473. The cubic root of 866195139 is about 953.2465615216.

The spelling of 866195139 in words is "eight hundred sixty-six million, one hundred ninety-five thousand, one hundred thirty-nine".