309898091 has 2 divisors, whose sum is σ = 309898092. Its totient is φ = 309898090.

The previous prime is 309898079. The next prime is 309898109. The reversal of 309898091 is 190898903.

Together with next prime (309898109) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 309898091 - 2⁶ = 309898027 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (309898591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 154949045 + 154949046.

It is an arithmetic number, because the mean of its divisors is an integer number (154949046).

Almost surely, 2^309898091 is an apocalyptic number.

309898091 is a deficient number, since it is larger than the sum of its proper divisors (1).

309898091 is an equidigital number, since it uses as much as digits as its factorization.

309898091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 139968, while the sum is 47.

The square root of 309898091 is about 17603.9226026474. The cubic root of 309898091 is about 676.7157747314.

The spelling of 309898091 in words is "three hundred nine million, eight hundred ninety-eight thousand, ninety-one".