81702180464 has 20 divisors (see below), whose sum is σ = 160301748960. Its totient is φ = 40333987200.

The previous prime is 81702180463. The next prime is 81702180563. The reversal of 81702180464 is 46408120718.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81702180463) 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, 32317637 + ... + 32320164.

It is an arithmetic number, because the mean of its divisors is an integer number (8015087448).

Almost surely, 2^81702180464 is an apocalyptic number.

It is an amenable number.

81702180464 is a deficient number, since it is larger than the sum of its proper divisors (78599568496).

81702180464 is a wasteful number, since it uses less digits than its factorization.

81702180464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64637888 (or 64637882 counting only the distinct ones).

The product of its (nonzero) digits is 86016, while the sum is 41.

The spelling of 81702180464 in words is "eighty-one billion, seven hundred two million, one hundred eighty thousand, four hundred sixty-four".