81860998016 has 32 divisors (see below), whose sum is σ = 186379952880. Its totient is φ = 35083284480.

The previous prime is 81860997989. The next prime is 81860998019. The reversal of 81860998016 is 61089906818.

It is a tau number, because it is divible by the number of its divisors (32).

It is a Harshad number since it is a multiple of its sum of digits (56).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81860998019) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 45680465 + ... + 45682256.

Almost surely, 2^81860998016 is an apocalyptic number.

It is an amenable number.

81860998016 is an abundant number, since it is smaller than the sum of its proper divisors (104518954864).

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

81860998016 is an equidigital number, since it uses as much as digits as its factorization.

81860998016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91362742 (or 91362730 counting only the distinct ones).

The product of its (nonzero) digits is 1492992, while the sum is 56.

The spelling of 81860998016 in words is "eighty-one billion, eight hundred sixty million, nine hundred ninety-eight thousand, sixteen".