81495493632 has 352 divisors, whose sum is σ = 276751779840. Its totient is φ = 23206625280.

The previous prime is 81495493609. The next prime is 81495493643. The reversal of 81495493632 is 23639459418.

81495493632 is a `hidden beast` number, since 8 + 1 + 4 + 95 + 493 + 63 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 83413528 + ... + 83414504.

Almost surely, 2^81495493632 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 81495493632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (138375889920).

81495493632 is an abundant number, since it is smaller than the sum of its proper divisors (195256286208).

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

81495493632 is a wasteful number, since it uses less digits than its factorization.

81495493632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1444 (or 1420 counting only the distinct ones).

The product of its digits is 5598720, while the sum is 54.

The spelling of 81495493632 in words is "eighty-one billion, four hundred ninety-five million, four hundred ninety-three thousand, six hundred thirty-two".