1218138956772 has 48 divisors (see below), whose sum is σ = 2851355572800. Its totient is φ = 404758062720.

The previous prime is 1218138956693. The next prime is 1218138956779. The reversal of 1218138956772 is 2776598318121.

It is not an unprimeable number, because it can be changed into a prime (1218138956779) 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, 4943247 + ... + 5183817.

It is an arithmetic number, because the mean of its divisors is an integer number (59403241100).

Almost surely, 2^{1218138956772} is an apocalyptic number.

1218138956772 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1218138956772 is an abundant number, since it is smaller than the sum of its proper divisors (1633216616028).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1218138956772 is a wasteful number, since it uses less digits than its factorization.

1218138956772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 241916 (or 241914 counting only the distinct ones).

The product of its digits is 10160640, while the sum is 60.

The spelling of 1218138956772 in words is "one trillion, two hundred eighteen billion, one hundred thirty-eight million, nine hundred fifty-six thousand, seven hundred seventy-two".