81500488 has 24 divisors (see below), whose sum is σ = 157916790. Its totient is φ = 39432000.

The previous prime is 81500483. The next prime is 81500513. The reversal of 81500488 is 88400518.

It can be written as a sum of positive squares in only one way, i.e., 56280004 + 25220484 = 7502^2 + 5022^2 .

It is not an unprimeable number, because it can be changed into a prime (81500483) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2388 + ... + 12988.

Almost surely, 2^81500488 is an apocalyptic number.

It is an amenable number.

81500488 is a deficient number, since it is larger than the sum of its proper divisors (76416302).

81500488 is a wasteful number, since it uses less digits than its factorization.

81500488 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10669 (or 10634 counting only the distinct ones).

The product of its (nonzero) digits is 10240, while the sum is 34.

The square root of 81500488 is about 9027.7620704137. The cubic root of 81500488 is about 433.5641883660.

The spelling of 81500488 in words is "eighty-one million, five hundred thousand, four hundred eighty-eight".