1231143205 has 16 divisors (see below), whose sum is σ = 1494702720. Its totient is φ = 973429312.

The previous prime is 1231143197. The next prime is 1231143223. The reversal of 1231143205 is 5023411321.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 1231143205 - 2³ = 1231143197 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 145347 + ... + 153583.

It is an arithmetic number, because the mean of its divisors is an integer number (93418920).

Almost surely, 2^1231143205 is an apocalyptic number.

It is an amenable number.

1231143205 is a deficient number, since it is larger than the sum of its proper divisors (263559515).

1231143205 is a wasteful number, since it uses less digits than its factorization.

1231143205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8588.

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 1231143205 is about 35087.6503203050. The cubic root of 1231143205 is about 1071.7731118944.

Adding to 1231143205 its reverse (5023411321), we get a palindrome (6254554526).

The spelling of 1231143205 in words is "one billion, two hundred thirty-one million, one hundred forty-three thousand, two hundred five".