81950880 has 288 divisors, whose sum is σ = 304057152. Its totient is φ = 18472960.

The previous prime is 81950873. The next prime is 81950927. The reversal of 81950880 is 8805918.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 987319 + ... + 987401.

It is an arithmetic number, because the mean of its divisors is an integer number (1055754).

Almost surely, 2^81950880 is an apocalyptic number.

81950880 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 81950880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (152028576).

81950880 is an abundant number, since it is smaller than the sum of its proper divisors (222106272).

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

81950880 is a wasteful number, since it uses less digits than its factorization.

81950880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140 (or 121 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 39.

The square root of 81950880 is about 9052.6725335671. The cubic root of 81950880 is about 434.3613829039.

The spelling of 81950880 in words is "eighty-one million, nine hundred fifty thousand, eight hundred eighty".