81211022440321 has 8 divisors (see below), whose sum is σ = 84069301536000. Its totient is φ = 78356603278800.

The previous prime is 81211022440291. The next prime is 81211022440337. The reversal of 81211022440321 is 12304422011218.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 81211022440321 - 2⁷ = 81211022440193 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81211022440351) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 964940721 + ... + 965024878.

It is an arithmetic number, because the mean of its divisors is an integer number (10508662692000).

Almost surely, 2^{81211022440321} is an apocalyptic number.

It is an amenable number.

81211022440321 is a deficient number, since it is larger than the sum of its proper divisors (2858279095679).

81211022440321 is a wasteful number, since it uses less digits than its factorization.

81211022440321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1929967079.

The product of its (nonzero) digits is 6144, while the sum is 31.

Adding to 81211022440321 its reverse (12304422011218), we get a palindrome (93515444451539).

The spelling of 81211022440321 in words is "eighty-one trillion, two hundred eleven billion, twenty-two million, four hundred forty thousand, three hundred twenty-one".