81450660 has 48 divisors (see below), whose sum is σ = 228920832. Its totient is φ = 21638400.

The previous prime is 81450637. The next prime is 81450673. The reversal of 81450660 is 6605418.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14445 + ... + 19275.

It is an arithmetic number, because the mean of its divisors is an integer number (4769184).

Almost surely, 2^81450660 is an apocalyptic number.

It is an amenable number.

81450660 is an abundant number, since it is smaller than the sum of its proper divisors (147470172).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81450660 is a wasteful number, since it uses less digits than its factorization.

81450660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5124 (or 5122 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 30.

The square root of 81450660 is about 9025.0019390580. The cubic root of 81450660 is about 433.4758124511.

The spelling of 81450660 in words is "eighty-one million, four hundred fifty thousand, six hundred sixty".