1218755989 has 16 divisors (see below), whose sum is σ = 1355109120. Its totient is φ = 1086845760.

The previous prime is 1218755933. The next prime is 1218756089. The reversal of 1218755989 is 9895578121.

It is not a de Polignac number, because 1218755989 - 2²⁹ = 681885077 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1218705989) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 131967 + ... + 140899.

It is an arithmetic number, because the mean of its divisors is an integer number (84694320).

Almost surely, 2^1218755989 is an apocalyptic number.

It is an amenable number.

1218755989 is a deficient number, since it is larger than the sum of its proper divisors (136353131).

1218755989 is a wasteful number, since it uses less digits than its factorization.

1218755989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9180.

The product of its digits is 1814400, while the sum is 55.

The square root of 1218755989 is about 34910.6858855566. The cubic root of 1218755989 is about 1068.1664200936.

The spelling of 1218755989 in words is "one billion, two hundred eighteen million, seven hundred fifty-five thousand, nine hundred eighty-nine".