81680590102 has 4 divisors (see below), whose sum is σ = 122520885156. Its totient is φ = 40840295050.

The previous prime is 81680590093. The next prime is 81680590109. The reversal of 81680590102 is 20109508618.

It is a semiprime because it is the product of two primes.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81680590109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20420147524 + ... + 20420147527.

It is an arithmetic number, because the mean of its divisors is an integer number (30630221289).

Almost surely, 2^81680590102 is an apocalyptic number.

81680590102 is a deficient number, since it is larger than the sum of its proper divisors (40840295054).

81680590102 is a wasteful number, since it uses less digits than its factorization.

81680590102 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40840295053.

The product of its (nonzero) digits is 34560, while the sum is 40.

The spelling of 81680590102 in words is "eighty-one billion, six hundred eighty million, five hundred ninety thousand, one hundred two".