1231930289 has 2 divisors, whose sum is σ = 1231930290. Its totient is φ = 1231930288.

The previous prime is 1231930267. The next prime is 1231930291. The reversal of 1231930289 is 9820391321.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1114424689 + 117505600 = 33383^2 + 10840^2 .

It is a cyclic number.

It is not a de Polignac number, because 1231930289 - 2¹² = 1231926193 is a prime.

Together with 1231930291, 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 (1231933289) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 615965144 + 615965145.

It is an arithmetic number, because the mean of its divisors is an integer number (615965145).

Almost surely, 2^1231930289 is an apocalyptic number.

It is an amenable number.

1231930289 is a deficient number, since it is larger than the sum of its proper divisors (1).

1231930289 is an equidigital number, since it uses as much as digits as its factorization.

1231930289 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23328, while the sum is 38.

The square root of 1231930289 is about 35098.8644973025. The cubic root of 1231930289 is about 1072.0014621949.

The spelling of 1231930289 in words is "one billion, two hundred thirty-one million, nine hundred thirty thousand, two hundred eighty-nine".