81459353563 has 12 divisors (see below), whose sum is σ = 95183780160. Its totient is φ = 69509189232.

The previous prime is 81459353561. The next prime is 81459353567. The reversal of 81459353563 is 36535395418.

It is not a de Polignac number, because 81459353563 - 2¹ = 81459353561 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81459353563.

It is not an unprimeable number, because it can be changed into a prime (81459353561) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3716508 + ... + 3738361.

It is an arithmetic number, because the mean of its divisors is an integer number (7931981680).

Almost surely, 2^81459353563 is an apocalyptic number.

81459353563 is a deficient number, since it is larger than the sum of its proper divisors (13724426597).

81459353563 is a wasteful number, since it uses less digits than its factorization.

81459353563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7455106 (or 7455099 counting only the distinct ones).

The product of its digits is 5832000, while the sum is 52.

The spelling of 81459353563 in words is "eighty-one billion, four hundred fifty-nine million, three hundred fifty-three thousand, five hundred sixty-three".