81225845240 has 16 divisors (see below), whose sum is σ = 182758151880. Its totient is φ = 32490338080.

The previous prime is 81225845179. The next prime is 81225845279. The reversal of 81225845240 is 4254852218.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1015323026 + ... + 1015323105.

Almost surely, 2^81225845240 is an apocalyptic number.

It is an amenable number.

81225845240 is an abundant number, since it is smaller than the sum of its proper divisors (101532306640).

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

81225845240 is a wasteful number, since it uses less digits than its factorization.

81225845240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2030646142 (or 2030646138 counting only the distinct ones).

The product of its (nonzero) digits is 204800, while the sum is 41.

The spelling of 81225845240 in words is "eighty-one billion, two hundred twenty-five million, eight hundred forty-five thousand, two hundred forty".