81172678224 has 160 divisors (see below), whose sum is σ = 232085145600. Its totient is φ = 24241351680.

The previous prime is 81172678219. The next prime is 81172678231. The reversal of 81172678224 is 42287627118.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 27486732 + ... + 27489684.

It is an arithmetic number, because the mean of its divisors is an integer number (1450532160).

Almost surely, 2^81172678224 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 81172678224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (116042572800).

81172678224 is an abundant number, since it is smaller than the sum of its proper divisors (150912467376).

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

81172678224 is a wasteful number, since it uses less digits than its factorization.

81172678224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3713 (or 3707 counting only the distinct ones).

The product of its digits is 602112, while the sum is 48.

The spelling of 81172678224 in words is "eighty-one billion, one hundred seventy-two million, six hundred seventy-eight thousand, two hundred twenty-four".