81021212018 has 32 divisors (see below), whose sum is σ = 124197086592. Its totient is φ = 39634560000.

The previous prime is 81021212017. The next prime is 81021212021.

81021212018 is nontrivially palindromic in base 10.

It is not an unprimeable number, because it can be changed into a prime (81021212011) 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, 5880005 + ... + 5893767.

It is an arithmetic number, because the mean of its divisors is an integer number (3881158956).

Almost surely, 2^81021212018 is an apocalyptic number.

81021212018 is a deficient number, since it is larger than the sum of its proper divisors (43175874574).

81021212018 is a wasteful number, since it uses less digits than its factorization.

81021212018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14210.

The product of its (nonzero) digits is 512, while the sum is 26.

The spelling of 81021212018 in words is "eighty-one billion, twenty-one million, two hundred twelve thousand, eighteen".