81754767855 has 32 divisors (see below), whose sum is σ = 145371283200. Its totient is φ = 43593700896.

The previous prime is 81754767839. The next prime is 81754767943. The reversal of 81754767855 is 55876745718.

81754767855 is a `hidden beast` number, since 8 + 1 + 7 + 547 + 6 + 7 + 85 + 5 = 666.

It is not a de Polignac number, because 81754767855 - 2⁴ = 81754767839 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 81754767792 and 81754767801.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 636016 + ... + 753674.

It is an arithmetic number, because the mean of its divisors is an integer number (4542852600).

Almost surely, 2^81754767855 is an apocalyptic number.

81754767855 is a deficient number, since it is larger than the sum of its proper divisors (63616515345).

81754767855 is a wasteful number, since it uses less digits than its factorization.

81754767855 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122820 (or 122814 counting only the distinct ones).

The product of its digits is 65856000, while the sum is 63.

The spelling of 81754767855 in words is "eighty-one billion, seven hundred fifty-four million, seven hundred sixty-seven thousand, eight hundred fifty-five".