81245985918 has 32 divisors (see below), whose sum is σ = 171308701440. Its totient is φ = 25616949120.

The previous prime is 81245985917. The next prime is 81245985941. The reversal of 81245985918 is 81958954218.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81245985911) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 477003 + ... + 624518.

It is an arithmetic number, because the mean of its divisors is an integer number (5353396920).

Almost surely, 2^81245985918 is an apocalyptic number.

81245985918 is an abundant number, since it is smaller than the sum of its proper divisors (90062715522).

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

81245985918 is a wasteful number, since it uses less digits than its factorization.

81245985918 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1102192.

The product of its digits is 8294400, while the sum is 60.

The spelling of 81245985918 in words is "eighty-one billion, two hundred forty-five million, nine hundred eighty-five thousand, nine hundred eighteen".