81466500 has 48 divisors (see below), whose sum is σ = 237234816. Its totient is φ = 21724000.

The previous prime is 81466493. The next prime is 81466501. The reversal of 81466500 is 566418.

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

It is not an unprimeable number, because it can be changed into a prime (81466501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25656 + ... + 28655.

It is an arithmetic number, because the mean of its divisors is an integer number (4942392).

Almost surely, 2^81466500 is an apocalyptic number.

It is an amenable number.

81466500 is an abundant number, since it is smaller than the sum of its proper divisors (155768316).

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

81466500 is a wasteful number, since it uses less digits than its factorization.

81466500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54333 (or 54321 counting only the distinct ones).

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

The square root of 81466500 is about 9025.8794585348. The cubic root of 81466500 is about 433.5039104916.

The spelling of 81466500 in words is "eighty-one million, four hundred sixty-six thousand, five hundred".