1309481749 has 2 divisors, whose sum is σ = 1309481750. Its totient is φ = 1309481748.

The previous prime is 1309481743. The next prime is 1309481857. The reversal of 1309481749 is 9471849031.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1170666225 + 138815524 = 34215^2 + 11782^2 .

It is a cyclic number.

It is not a de Polignac number, because 1309481749 - 2³ = 1309481741 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1309481699 and 1309481708.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1309481741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 654740874 + 654740875.

It is an arithmetic number, because the mean of its divisors is an integer number (654740875).

Almost surely, 2^1309481749 is an apocalyptic number.

It is an amenable number.

1309481749 is a deficient number, since it is larger than the sum of its proper divisors (1).

1309481749 is an equidigital number, since it uses as much as digits as its factorization.

1309481749 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 217728, while the sum is 46.

The square root of 1309481749 is about 36186.7620684692. The cubic root of 1309481749 is about 1094.0398717347.

The spelling of 1309481749 in words is "one billion, three hundred nine million, four hundred eighty-one thousand, seven hundred forty-nine".