81973370880 has 168 divisors, whose sum is σ = 284158285632. Its totient is φ = 21859467264.

The previous prime is 81973370873. The next prime is 81973370891. The reversal of 81973370880 is 8807337918.

81973370880 is a `hidden beast` number, since 8 + 197 + 3 + 370 + 8 + 80 = 666.

It is a super-5 number, since 5×81973370880⁵ (a number of 56 digits) contains 55555 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 257457 + ... + 479823.

Almost surely, 2^81973370880 is an apocalyptic number.

81973370880 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81973370880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (142079142816).

81973370880 is an abundant number, since it is smaller than the sum of its proper divisors (202184914752).

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

81973370880 is a wasteful number, since it uses less digits than its factorization.

81973370880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222404 (or 222377 counting only the distinct ones).

The product of its (nonzero) digits is 2032128, while the sum is 54.

The spelling of 81973370880 in words is "eighty-one billion, nine hundred seventy-three million, three hundred seventy thousand, eight hundred eighty".