81336555567 has 40 divisors (see below), whose sum is σ = 125633219712. Its totient is φ = 52386912000.

The previous prime is 81336555511. The next prime is 81336555613. The reversal of 81336555567 is 76555563318.

81336555567 is a `hidden beast` number, since 8 + 1 + 3 + 36 + 55 + 556 + 7 = 666.

It is not a de Polignac number, because 81336555567 - 2¹⁶ = 81336490031 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81336555367) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1482163 + ... + 1536059.

Almost surely, 2^81336555567 is an apocalyptic number.

81336555567 is a deficient number, since it is larger than the sum of its proper divisors (44296664145).

81336555567 is a wasteful number, since it uses less digits than its factorization.

81336555567 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54541 (or 54532 counting only the distinct ones).

The product of its digits is 11340000, while the sum is 54.

The spelling of 81336555567 in words is "eighty-one billion, three hundred thirty-six million, five hundred fifty-five thousand, five hundred sixty-seven".