1218338121 has 128 divisors (see below), whose sum is σ = 2327592960. Its totient is φ = 545875200.

The previous prime is 1218338119. The next prime is 1218338131.

1218338121 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 1218338121 - 2¹ = 1218338119 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1218338131) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 7474386 + ... + 7474548.

It is an arithmetic number, because the mean of its divisors is an integer number (18184320).

Almost surely, 2^1218338121 is an apocalyptic number.

1218338121 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1218338121 is a deficient number, since it is larger than the sum of its proper divisors (1109254839).

1218338121 is a wasteful number, since it uses less digits than its factorization.

1218338121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 347.

The product of its digits is 2304, while the sum is 30.

The square root of 1218338121 is about 34904.7005573748. The cubic root of 1218338121 is about 1068.0443274045.

The spelling of 1218338121 in words is "one billion, two hundred eighteen million, three hundred thirty-eight thousand, one hundred twenty-one".