81761142480 has 80 divisors (see below), whose sum is σ = 254924755200. Its totient is φ = 21676931584.

The previous prime is 81761142457. The next prime is 81761142511. The reversal of 81761142480 is 8424116718.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 943080 + ... + 1026119.

It is an arithmetic number, because the mean of its divisors is an integer number (3186559440).

Almost surely, 2^81761142480 is an apocalyptic number.

81761142480 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

81761142480 is an abundant number, since it is smaller than the sum of its proper divisors (173163612720).

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

81761142480 is a wasteful number, since it uses less digits than its factorization.

81761142480 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1969388 (or 1969382 counting only the distinct ones).

The product of its (nonzero) digits is 86016, while the sum is 42.

The spelling of 81761142480 in words is "eighty-one billion, seven hundred sixty-one million, one hundred forty-two thousand, four hundred eighty".