81556445052 has 60 divisors (see below), whose sum is σ = 216818346360. Its totient is φ = 26724704544.

The previous prime is 81556445051. The next prime is 81556445057. The reversal of 81556445052 is 25054465518.

81556445052 is a `hidden beast` number, since 8 + 1 + 556 + 4 + 45 + 0 + 52 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 81556444989 and 81556445007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81556445051) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 2114083 + ... + 2152314.

It is an arithmetic number, because the mean of its divisors is an integer number (3613639106).

Almost surely, 2^81556445052 is an apocalyptic number.

It is an amenable number.

81556445052 is an abundant number, since it is smaller than the sum of its proper divisors (135261901308).

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

81556445052 is a wasteful number, since it uses less digits than its factorization.

81556445052 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4266472 (or 4266461 counting only the distinct ones).

The product of its (nonzero) digits is 960000, while the sum is 45.

The spelling of 81556445052 in words is "eighty-one billion, five hundred fifty-six million, four hundred forty-five thousand, fifty-two".