1231390873 has 2 divisors, whose sum is σ = 1231390874. Its totient is φ = 1231390872.

The previous prime is 1231390819. The next prime is 1231390879. The reversal of 1231390873 is 3780931321.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 987656329 + 243734544 = 31427^2 + 15612^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1231390873 is a prime.

It is not a weakly prime, because it can be changed into another prime (1231390879) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 615695436 + 615695437.

It is an arithmetic number, because the mean of its divisors is an integer number (615695437).

Almost surely, 2^1231390873 is an apocalyptic number.

It is an amenable number.

1231390873 is a deficient number, since it is larger than the sum of its proper divisors (1).

1231390873 is an equidigital number, since it uses as much as digits as its factorization.

1231390873 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27216, while the sum is 37.

The square root of 1231390873 is about 35091.1794187656. The cubic root of 1231390873 is about 1071.8449762950.

The spelling of 1231390873 in words is "one billion, two hundred thirty-one million, three hundred ninety thousand, eight hundred seventy-three".