81814663982 has 8 divisors (see below), whose sum is σ = 124275439200. Its totient is φ = 40389517584.

The previous prime is 81814663967. The next prime is 81814663991. The reversal of 81814663982 is 28936641818.

It is a happy number.

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 polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 258907007 + ... + 258907322.

It is an arithmetic number, because the mean of its divisors is an integer number (15534429900).

Almost surely, 2^81814663982 is an apocalyptic number.

81814663982 is a deficient number, since it is larger than the sum of its proper divisors (42460775218).

81814663982 is a wasteful number, since it uses less digits than its factorization.

81814663982 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 517814410.

The product of its digits is 3981312, while the sum is 56.

The spelling of 81814663982 in words is "eighty-one billion, eight hundred fourteen million, six hundred sixty-three thousand, nine hundred eighty-two".