913309561 has 2 divisors, whose sum is σ = 913309562. Its totient is φ = 913309560.

The previous prime is 913309559. The next prime is 913309567. The reversal of 913309561 is 165903319.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 706496400 + 206813161 = 26580^2 + 14381^2 .

It is an emirp because it is prime and its reverse (165903319) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 913309561 - 2¹ = 913309559 is a prime.

Together with 913309559, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 913309561.

It is not a weakly prime, because it can be changed into another prime (913309567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 456654780 + 456654781.

It is an arithmetic number, because the mean of its divisors is an integer number (456654781).

Almost surely, 2^913309561 is an apocalyptic number.

It is an amenable number.

913309561 is a deficient number, since it is larger than the sum of its proper divisors (1).

913309561 is an equidigital number, since it uses as much as digits as its factorization.

913309561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 21870, while the sum is 37.

The square root of 913309561 is about 30221.0119122441. The cubic root of 913309561 is about 970.2254625229.

The spelling of 913309561 in words is "nine hundred thirteen million, three hundred nine thousand, five hundred sixty-one".