1309481857 has 2 divisors, whose sum is σ = 1309481858. Its totient is φ = 1309481856.

The previous prime is 1309481749. The next prime is 1309481869. The reversal of 1309481857 is 7581849031.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 834285456 + 475196401 = 28884^2 + 21799^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1309481857 is a prime.

It is not a weakly prime, because it can be changed into another prime (1309481357) 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, 654740928 + 654740929.

It is an arithmetic number, because the mean of its divisors is an integer number (654740929).

Almost surely, 2^1309481857 is an apocalyptic number.

It is an amenable number.

1309481857 is a deficient number, since it is larger than the sum of its proper divisors (1).

1309481857 is an equidigital number, since it uses as much as digits as its factorization.

1309481857 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 241920, while the sum is 46.

The square root of 1309481857 is about 36186.7635607276. The cubic root of 1309481857 is about 1094.0399018118.

The spelling of 1309481857 in words is "one billion, three hundred nine million, four hundred eighty-one thousand, eight hundred fifty-seven".