81031576032 has 288 divisors, whose sum is σ = 268822610784. Its totient is φ = 22880256000.

The previous prime is 81031576027. The next prime is 81031576057. The reversal of 81031576032 is 23067513018.

81031576032 is a `hidden beast` number, since 8 + 10 + 31 + 5 + 7 + 603 + 2 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a super-2 number, since 2×81031576032² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5432008 + ... + 5446904.

It is an arithmetic number, because the mean of its divisors is an integer number (933411843).

Almost surely, 2^81031576032 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81031576032, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (134411305392).

81031576032 is an abundant number, since it is smaller than the sum of its proper divisors (187791034752).

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

81031576032 is a wasteful number, since it uses less digits than its factorization.

81031576032 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15042 (or 15031 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The spelling of 81031576032 in words is "eighty-one billion, thirty-one million, five hundred seventy-six thousand, thirty-two".