1264616809 has 2 divisors, whose sum is σ = 1264616810. Its totient is φ = 1264616808.

The previous prime is 1264616807. The next prime is 1264616813. The reversal of 1264616809 is 9086164621.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 971693584 + 292923225 = 31172^2 + 17115^2 .

It is a cyclic number.

It is not a de Polignac number, because 1264616809 - 2¹ = 1264616807 is a prime.

Together with 1264616807, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1264616807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 632308404 + 632308405.

It is an arithmetic number, because the mean of its divisors is an integer number (632308405).

Almost surely, 2^1264616809 is an apocalyptic number.

It is an amenable number.

1264616809 is a deficient number, since it is larger than the sum of its proper divisors (1).

1264616809 is an equidigital number, since it uses as much as digits as its factorization.

1264616809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 124416, while the sum is 43.

The square root of 1264616809 is about 35561.4511655528. The cubic root of 1264616809 is about 1081.3998791019.

The spelling of 1264616809 in words is "one billion, two hundred sixty-four million, six hundred sixteen thousand, eight hundred nine".