81667258576 has 40 divisors (see below), whose sum is σ = 163493964288. Its totient is φ = 39477840000.

The previous prime is 81667258571. The next prime is 81667258591. The reversal of 81667258576 is 67585276618.

It is a super-2 number, since 2×81667258576² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81667258571) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 431526 + ... + 591226.

Almost surely, 2^81667258576 is an apocalyptic number.

It is an amenable number.

81667258576 is an abundant number, since it is smaller than the sum of its proper divisors (81826705712).

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

81667258576 is a wasteful number, since it uses less digits than its factorization.

81667258576 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160771 (or 160765 counting only the distinct ones).

The product of its digits is 33868800, while the sum is 61.

The spelling of 81667258576 in words is "eighty-one billion, six hundred sixty-seven million, two hundred fifty-eight thousand, five hundred seventy-six".