1217274809 has 2 divisors, whose sum is σ = 1217274810. Its totient is φ = 1217274808.

The previous prime is 1217274757. The next prime is 1217274811. The reversal of 1217274809 is 9084727121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 852464809 + 364810000 = 29197^2 + 19100^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1217274809 is a prime.

Together with 1217274811, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1217274829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 608637404 + 608637405.

It is an arithmetic number, because the mean of its divisors is an integer number (608637405).

Almost surely, 2^1217274809 is an apocalyptic number.

It is an amenable number.

1217274809 is a deficient number, since it is larger than the sum of its proper divisors (1).

1217274809 is an equidigital number, since it uses as much as digits as its factorization.

1217274809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 56448, while the sum is 41.

The square root of 1217274809 is about 34889.4655877673. The cubic root of 1217274809 is about 1067.7335229087.

The spelling of 1217274809 in words is "one billion, two hundred seventeen million, two hundred seventy-four thousand, eight hundred nine".