81387489982 has 8 divisors (see below), whose sum is σ = 122093291952. Its totient is φ = 40689726000.

The previous prime is 81387489949. The next prime is 81387490001. The reversal of 81387489982 is 28998478318.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1984119 + ... + 2024722.

It is an arithmetic number, because the mean of its divisors is an integer number (15261661494).

Almost surely, 2^81387489982 is an apocalyptic number.

81387489982 is a deficient number, since it is larger than the sum of its proper divisors (40705801970).

81387489982 is a wasteful number, since it uses less digits than its factorization.

81387489982 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4018994.

The product of its digits is 55738368, while the sum is 67.

The spelling of 81387489982 in words is "eighty-one billion, three hundred eighty-seven million, four hundred eighty-nine thousand, nine hundred eighty-two".