81543041493 has 8 divisors (see below), whose sum is σ = 112473160800. Its totient is φ = 52487474928.

The previous prime is 81543041479. The next prime is 81543041497. The reversal of 81543041493 is 39414034518.

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

It is not a de Polignac number, because 81543041493 - 2¹² = 81543037397 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81543041497) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 468638083 + ... + 468638256.

It is an arithmetic number, because the mean of its divisors is an integer number (14059145100).

Almost surely, 2^81543041493 is an apocalyptic number.

It is an amenable number.

81543041493 is a deficient number, since it is larger than the sum of its proper divisors (30930119307).

81543041493 is a wasteful number, since it uses less digits than its factorization.

81543041493 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 937276371.

The product of its (nonzero) digits is 207360, while the sum is 42.

The spelling of 81543041493 in words is "eighty-one billion, five hundred forty-three million, forty-one thousand, four hundred ninety-three".