81563670244 has 24 divisors (see below), whose sum is σ = 164651901120. Its totient is φ = 34629167136.

The previous prime is 81563670197. The next prime is 81563670257. The reversal of 81563670244 is 44207636518.

It is a junction number, because it is equal to n+sod(n) for n = 81563670194 and 81563670203.

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, 13609099 + ... + 13615090.

It is an arithmetic number, because the mean of its divisors is an integer number (6860495880).

Almost surely, 2^81563670244 is an apocalyptic number.

It is an amenable number.

81563670244 is an abundant number, since it is smaller than the sum of its proper divisors (83088230876).

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

81563670244 is a wasteful number, since it uses less digits than its factorization.

81563670244 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27224307 (or 27224305 counting only the distinct ones).

The product of its (nonzero) digits is 967680, while the sum is 46.

The spelling of 81563670244 in words is "eighty-one billion, five hundred sixty-three million, six hundred seventy thousand, two hundred forty-four".