81138767455 has 16 divisors (see below), whose sum is σ = 102561786720. Its totient is φ = 61452217728.

The previous prime is 81138767443. The next prime is 81138767459. The reversal of 81138767455 is 55476783118.

It is a cyclic number.

It is not a de Polignac number, because 81138767455 - 2²⁷ = 81004549727 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 81138767396 and 81138767405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81138767459) 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, 155872 + ... + 431941.

It is an arithmetic number, because the mean of its divisors is an integer number (6410111670).

Almost surely, 2^81138767455 is an apocalyptic number.

81138767455 is a deficient number, since it is larger than the sum of its proper divisors (21423019265).

81138767455 is a wasteful number, since it uses less digits than its factorization.

81138767455 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 589290.

The product of its digits is 5644800, while the sum is 55.

The spelling of 81138767455 in words is "eighty-one billion, one hundred thirty-eight million, seven hundred sixty-seven thousand, four hundred fifty-five".