1218116553 has 8 divisors (see below), whose sum is σ = 1668051648. Its totient is φ = 790129584.

The previous prime is 1218116527. The next prime is 1218116597. The reversal of 1218116553 is 3556118121.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1218116553 - 2⁸ = 1218116297 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1218111553) 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 in 7 ways as a sum of consecutive naturals, for example, 5486901 + ... + 5487122.

It is an arithmetic number, because the mean of its divisors is an integer number (208506456).

Almost surely, 2^1218116553 is an apocalyptic number.

It is an amenable number.

1218116553 is a deficient number, since it is larger than the sum of its proper divisors (449935095).

1218116553 is a wasteful number, since it uses less digits than its factorization.

1218116553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10974063.

The product of its digits is 7200, while the sum is 33.

The square root of 1218116553 is about 34901.5265138933. The cubic root of 1218116553 is about 1067.9795783313.

The spelling of 1218116553 in words is "one billion, two hundred eighteen million, one hundred sixteen thousand, five hundred fifty-three".