81136631055 has 8 divisors (see below), whose sum is σ = 129818609712. Its totient is φ = 43272869888.

The previous prime is 81136631029. The next prime is 81136631087. The reversal of 81136631055 is 55013663118.

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

It is a cyclic number.

It is not a de Polignac number, because 81136631055 - 2²¹ = 81134533903 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2704554354 + ... + 2704554383.

It is an arithmetic number, because the mean of its divisors is an integer number (16227326214).

Almost surely, 2^81136631055 is an apocalyptic number.

81136631055 is a deficient number, since it is larger than the sum of its proper divisors (48681978657).

81136631055 is a wasteful number, since it uses less digits than its factorization.

81136631055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5409108745.

The product of its (nonzero) digits is 64800, while the sum is 39.

The spelling of 81136631055 in words is "eighty-one billion, one hundred thirty-six million, six hundred thirty-one thousand, fifty-five".