81243968943 has 8 divisors (see below), whose sum is σ = 108336592000. Its totient is φ = 54156995928.

The previous prime is 81243968933. The next prime is 81243968947. The reversal of 81243968943 is 34986934218.

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

It is not a de Polignac number, because 81243968943 - 2¹⁶ = 81243903407 is a prime.

It is a super-3 number, since 3×81243968943³ (a number of 34 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81243968947) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1378843 + ... + 1436556.

It is an arithmetic number, because the mean of its divisors is an integer number (13542074000).

Almost surely, 2^81243968943 is an apocalyptic number.

81243968943 is a deficient number, since it is larger than the sum of its proper divisors (27092623057).

81243968943 is a wasteful number, since it uses less digits than its factorization.

81243968943 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2825021.

The product of its digits is 8957952, while the sum is 57.

The spelling of 81243968943 in words is "eighty-one billion, two hundred forty-three million, nine hundred sixty-eight thousand, nine hundred forty-three".