861131223 has 8 divisors (see below), whose sum is σ = 1275750000. Its totient is φ = 574087464.

The previous prime is 861131221. The next prime is 861131233. The reversal of 861131223 is 322131168.

It is a happy number.

It is not a de Polignac number, because 861131223 - 2¹ = 861131221 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 31893749 = 861131223 / (8 + 6 + 1 + 1 + 3 + 1 + 2 + 2 + 3).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861131221) 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, 15946848 + ... + 15946901.

It is an arithmetic number, because the mean of its divisors is an integer number (159468750).

Almost surely, 2^861131223 is an apocalyptic number.

861131223 is a deficient number, since it is larger than the sum of its proper divisors (414618777).

861131223 is a wasteful number, since it uses less digits than its factorization.

861131223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31893758 (or 31893752 counting only the distinct ones).

The product of its digits is 1728, while the sum is 27.

The square root of 861131223 is about 29345.0374509899. The cubic root of 861131223 is about 951.3853188855.

The spelling of 861131223 in words is "eight hundred sixty-one million, one hundred thirty-one thousand, two hundred twenty-three".