81358711632 has 80 divisors (see below), whose sum is σ = 254759616960. Its totient is φ = 24654153600.

The previous prime is 81358711619. The next prime is 81358711649. The reversal of 81358711632 is 23611785318.

It is a happy number.

81358711632 is a `hidden beast` number, since 8 + 1 + 3 + 5 + 8 + 7 + 1 + 1 + 632 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8555719 + ... + 8565222.

It is an arithmetic number, because the mean of its divisors is an integer number (3184495212).

Almost surely, 2^81358711632 is an apocalyptic number.

It is an amenable number.

81358711632 is an abundant number, since it is smaller than the sum of its proper divisors (173400905328).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81358711632 is a wasteful number, since it uses less digits than its factorization.

81358711632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17120969 (or 17120957 counting only the distinct ones).

The product of its digits is 241920, while the sum is 45.

The spelling of 81358711632 in words is "eighty-one billion, three hundred fifty-eight million, seven hundred eleven thousand, six hundred thirty-two".