81450500 has 24 divisors (see below), whose sum is σ = 177888984. Its totient is φ = 32580000.

The previous prime is 81450487. The next prime is 81450533. The reversal of 81450500 is 505418.

It can be written as a sum of positive squares in 4 ways, for example, as 9132484 + 72318016 = 3022^2 + 8504^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 80951 + ... + 81950.

It is an arithmetic number, because the mean of its divisors is an integer number (7412041).

Almost surely, 2^81450500 is an apocalyptic number.

It is an amenable number.

81450500 is an abundant number, since it is smaller than the sum of its proper divisors (96438484).

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

81450500 is a wasteful number, since it uses less digits than its factorization.

81450500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162920 (or 162908 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 23.

The square root of 81450500 is about 9024.9930747896. The cubic root of 81450500 is about 433.4755286139.

Adding to 81450500 its reverse (505418), we get a palindrome (81955918).

The spelling of 81450500 in words is "eighty-one million, four hundred fifty thousand, five hundred".