81000011000018 has 32 divisors (see below), whose sum is σ = 133939216897920. Its totient is φ = 36431190351360.

The previous prime is 81000010999993. The next prime is 81000011000033.

81000011000018 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×81000011000018² (a number of 29 digits) contains 22 as substring.

81000011000018 is a strobogrammatic number because it is the same when read upside-down.

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, 6609755 + ... + 14341857.

It is an arithmetic number, because the mean of its divisors is an integer number (4185600528060).

Almost surely, 2^{81000011000018} is an apocalyptic number.

81000011000018 is a deficient number, since it is larger than the sum of its proper divisors (52939205897902).

81000011000018 is a wasteful number, since it uses less digits than its factorization.

81000011000018 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7737122.

The product of its (nonzero) digits is 64, while the sum is 20.

It can be divided in two parts, 8100001 and 1000018, that added together give a palindrome (9100019).

The spelling of 81000011000018 in words is "eighty-one trillion, eleven million, eighteen", and thus it is an aban number and an uban number.