81037485644 has 24 divisors (see below), whose sum is σ = 142456255200. Its totient is φ = 40336085504.

The previous prime is 81037485619. The next prime is 81037485647. The reversal of 81037485644 is 44658473018.

It is a junction number, because it is equal to n+sod(n) for n = 81037485592 and 81037485601.

It is not an unprimeable number, because it can be changed into a prime (81037485647) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 797882 + ... + 893694.

It is an arithmetic number, because the mean of its divisors is an integer number (5935677300).

Almost surely, 2^81037485644 is an apocalyptic number.

It is an amenable number.

81037485644 is a deficient number, since it is larger than the sum of its proper divisors (61418769556).

81037485644 is a wasteful number, since it uses less digits than its factorization.

81037485644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96769 (or 96767 counting only the distinct ones).

The product of its (nonzero) digits is 2580480, while the sum is 50.

The spelling of 81037485644 in words is "eighty-one billion, thirty-seven million, four hundred eighty-five thousand, six hundred forty-four".