81744672754872 has 48 divisors (see below), whose sum is σ = 221399678039280. Its totient is φ = 27247257360000.

The previous prime is 81744672754861. The next prime is 81744672754873. The reversal of 81744672754872 is 27845727644718.

81744672754872 is a `hidden beast` number, since 8 + 1 + 7 + 4 + 4 + 6 + 7 + 2 + 7 + 548 + 72 = 666.

It is a super-2 number, since 2×81744672754872² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a self number, because there is not a number n which added to its sum of digits gives 81744672754872.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81744672754873) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18099004 + ... + 22159947.

It is an arithmetic number, because the mean of its divisors is an integer number (4612493292485).

Almost surely, 2^{81744672754872} is an apocalyptic number.

It is an amenable number.

81744672754872 is an abundant number, since it is smaller than the sum of its proper divisors (139655005284408).

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

81744672754872 is a wasteful number, since it uses less digits than its factorization.

81744672754872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40287164 (or 40287157 counting only the distinct ones).

The product of its digits is 1180139520, while the sum is 72.

The spelling of 81744672754872 in words is "eighty-one trillion, seven hundred forty-four billion, six hundred seventy-two million, seven hundred fifty-four thousand, eight hundred seventy-two".