81385480 has 32 divisors (see below), whose sum is σ = 199765440. Its totient is φ = 29594560.

The previous prime is 81385463. The next prime is 81385481. The reversal of 81385480 is 8458318.

It is not an unprimeable number, because it can be changed into a prime (81385481) 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 7 ways as a sum of consecutive naturals, for example, 92044 + ... + 92923.

It is an arithmetic number, because the mean of its divisors is an integer number (6242670).

Almost surely, 2^81385480 is an apocalyptic number.

It is an amenable number.

81385480 is an abundant number, since it is smaller than the sum of its proper divisors (118379960).

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

81385480 is a wasteful number, since it uses less digits than its factorization.

81385480 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 184989 (or 184985 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 37.

The square root of 81385480 is about 9021.3901367805. The cubic root of 81385480 is about 433.3601535011.

The spelling of 81385480 in words is "eighty-one million, three hundred eighty-five thousand, four hundred eighty".