1216155559 has 2 divisors, whose sum is σ = 1216155560. Its totient is φ = 1216155558.

The previous prime is 1216155547. The next prime is 1216155569. The reversal of 1216155559 is 9555516121.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1216155559 - 2⁷ = 1216155431 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1216155509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 608077779 + 608077780.

It is an arithmetic number, because the mean of its divisors is an integer number (608077780).

Almost surely, 2^1216155559 is an apocalyptic number.

1216155559 is a deficient number, since it is larger than the sum of its proper divisors (1).

1216155559 is an equidigital number, since it uses as much as digits as its factorization.

1216155559 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 67500, while the sum is 40.

The square root of 1216155559 is about 34873.4219571295. The cubic root of 1216155559 is about 1067.4061722292.

The spelling of 1216155559 in words is "one billion, two hundred sixteen million, one hundred fifty-five thousand, five hundred fifty-nine".