309468661 has 2 divisors, whose sum is σ = 309468662. Its totient is φ = 309468660.

The previous prime is 309468619. The next prime is 309468667. The reversal of 309468661 is 166864903.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 285272100 + 24196561 = 16890^2 + 4919^2 .

It is an emirp because it is prime and its reverse (166864903) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 309468661 - 2⁹ = 309468149 is a prime.

It is a super-2 number, since 2×309468661² = 191541704282265842, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (309468667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 154734330 + 154734331.

It is an arithmetic number, because the mean of its divisors is an integer number (154734331).

Almost surely, 2^309468661 is an apocalyptic number.

It is an amenable number.

309468661 is a deficient number, since it is larger than the sum of its proper divisors (1).

309468661 is an equidigital number, since it uses as much as digits as its factorization.

309468661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 186624, while the sum is 43.

The square root of 309468661 is about 17591.7213768295. The cubic root of 309468661 is about 676.4030521543.

The spelling of 309468661 in words is "three hundred nine million, four hundred sixty-eight thousand, six hundred sixty-one".