81538204740 has 96 divisors (see below), whose sum is σ = 245436549120. Its totient is φ = 20160832896.

The previous prime is 81538204723. The next prime is 81538204771. The reversal of 81538204740 is 4740283518.

It is a junction number, because it is equal to n+sod(n) for n = 81538204692 and 81538204701.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 707322 + ... + 814481.

It is an arithmetic number, because the mean of its divisors is an integer number (2556630720).

Almost surely, 2^81538204740 is an apocalyptic number.

It is an amenable number.

81538204740 is an abundant number, since it is smaller than the sum of its proper divisors (163898344380).

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

81538204740 is a wasteful number, since it uses less digits than its factorization.

81538204740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1521881 (or 1521879 counting only the distinct ones).

The product of its (nonzero) digits is 215040, while the sum is 42.

The spelling of 81538204740 in words is "eighty-one billion, five hundred thirty-eight million, two hundred four thousand, seven hundred forty".