1231134221 has 2 divisors, whose sum is σ = 1231134222. Its totient is φ = 1231134220.

The previous prime is 1231134143. The next prime is 1231134227. The reversal of 1231134221 is 1224311321.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1098193321 + 132940900 = 33139^2 + 11530^2 .

It is a cyclic number.

It is not a de Polignac number, because 1231134221 - 2¹⁴ = 1231117837 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1231134193 and 1231134202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1231134227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 615567110 + 615567111.

It is an arithmetic number, because the mean of its divisors is an integer number (615567111).

Almost surely, 2^1231134221 is an apocalyptic number.

It is an amenable number.

1231134221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1231134221 is an equidigital number, since it uses as much as digits as its factorization.

1231134221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 288, while the sum is 20.

The square root of 1231134221 is about 35087.5222978198. The cubic root of 1231134221 is about 1071.7705048776.

Adding to 1231134221 its reverse (1224311321), we get a palindrome (2455445542).

The spelling of 1231134221 in words is "one billion, two hundred thirty-one million, one hundred thirty-four thousand, two hundred twenty-one".