1231333139 has 2 divisors, whose sum is σ = 1231333140. Its totient is φ = 1231333138.

The previous prime is 1231333111. The next prime is 1231333141. The reversal of 1231333139 is 9313331321.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1231333139 - 2¹⁶ = 1231267603 is a prime.

Together with 1231333141, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1231333109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 615666569 + 615666570.

It is an arithmetic number, because the mean of its divisors is an integer number (615666570).

Almost surely, 2^1231333139 is an apocalyptic number.

1231333139 is a deficient number, since it is larger than the sum of its proper divisors (1).

1231333139 is an equidigital number, since it uses as much as digits as its factorization.

1231333139 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4374, while the sum is 29.

The square root of 1231333139 is about 35090.3567807453. The cubic root of 1231333139 is about 1071.8282248133.

The spelling of 1231333139 in words is "one billion, two hundred thirty-one million, three hundred thirty-three thousand, one hundred thirty-nine".