1218131255516 has 12 divisors (see below), whose sum is σ = 2436262511088. Its totient is φ = 522056252352.

The previous prime is 1218131255491. The next prime is 1218131255533. The reversal of 1218131255516 is 6155521318121.

1218131255516 is an admirable number.

It is a super-3 number, since 3×1218131255516³ (a number of 37 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21752343821 + ... + 21752343876.

It is an arithmetic number, because the mean of its divisors is an integer number (203021875924).

Almost surely, 2^{1218131255516} is an apocalyptic number.

It is an amenable number.

1218131255516 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

1218131255516 is a wasteful number, since it uses less digits than its factorization.

1218131255516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43504687708 (or 43504687706 counting only the distinct ones).

The product of its digits is 72000, while the sum is 41.

The spelling of 1218131255516 in words is "one trillion, two hundred eighteen billion, one hundred thirty-one million, two hundred fifty-five thousand, five hundred sixteen".