309490109 has 2 divisors, whose sum is σ = 309490110. Its totient is φ = 309490108.

The previous prime is 309490091. The next prime is 309490123. The reversal of 309490109 is 901094903.

Together with previous prime (309490091) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 208889209 + 100600900 = 14453^2 + 10030^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-309490109 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (309490169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 154745054 + 154745055.

It is an arithmetic number, because the mean of its divisors is an integer number (154745055).

Almost surely, 2^309490109 is an apocalyptic number.

It is an amenable number.

309490109 is a deficient number, since it is larger than the sum of its proper divisors (1).

309490109 is an equidigital number, since it uses as much as digits as its factorization.

309490109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8748, while the sum is 35.

The square root of 309490109 is about 17592.3309711931. The cubic root of 309490109 is about 676.4186780311.

The spelling of 309490109 in words is "three hundred nine million, four hundred ninety thousand, one hundred nine".