866823231 has 4 divisors (see below), whose sum is σ = 1155764312. Its totient is φ = 577882152.

The previous prime is 866823227. The next prime is 866823233. The reversal of 866823231 is 132328668.

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

It is not a de Polignac number, because 866823231 - 2² = 866823227 is a prime.

It is a super-2 number, since 2×866823231² = 1502765027602558722, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 866823231.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (866823233) 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, 144470536 + ... + 144470541.

It is an arithmetic number, because the mean of its divisors is an integer number (288941078).

Almost surely, 2^866823231 is an apocalyptic number.

866823231 is a deficient number, since it is larger than the sum of its proper divisors (288941081).

866823231 is a wasteful number, since it uses less digits than its factorization.

866823231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 288941080.

The product of its digits is 82944, while the sum is 39.

The square root of 866823231 is about 29441.8618806624. The cubic root of 866823231 is about 953.4769106486.

The spelling of 866823231 in words is "eight hundred sixty-six million, eight hundred twenty-three thousand, two hundred thirty-one".