81947636662 has 8 divisors (see below), whose sum is σ = 122922954000. Its totient is φ = 40973318664.

The previous prime is 81947636623. The next prime is 81947636663. The reversal of 81947636662 is 26663674918.

It is a happy number.

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

It is a junction number, because it is equal to n+sod(n) for n = 81947636597 and 81947636606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81947636663) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8664 + ... + 404932.

It is an arithmetic number, because the mean of its divisors is an integer number (15365369250).

Almost surely, 2^81947636662 is an apocalyptic number.

81947636662 is a deficient number, since it is larger than the sum of its proper divisors (40975317338).

81947636662 is a wasteful number, since it uses less digits than its factorization.

81947636662 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 499670.

The product of its digits is 15676416, while the sum is 58.

The spelling of 81947636662 in words is "eighty-one billion, nine hundred forty-seven million, six hundred thirty-six thousand, six hundred sixty-two".