81312133121318 has 32 divisors (see below), whose sum is σ = 133104507465600. Its totient is φ = 36946648128960.

The previous prime is 81312133121299. The next prime is 81312133121341.

81312133121318 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×81312133121318² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2349840605 + ... + 2349875207.

It is an arithmetic number, because the mean of its divisors is an integer number (4159515858300).

Almost surely, 2^{81312133121318} is an apocalyptic number.

81312133121318 is a deficient number, since it is larger than the sum of its proper divisors (51792374344282).

81312133121318 is a wasteful number, since it uses less digits than its factorization.

81312133121318 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70292.

The product of its digits is 20736, while the sum is 38.

The spelling of 81312133121318 in words is "eighty-one trillion, three hundred twelve billion, one hundred thirty-three million, one hundred twenty-one thousand, three hundred eighteen".