81457445052 has 18 divisors (see below), whose sum is σ = 205906319528. Its totient is φ = 27152481672.

The previous prime is 81457445051. The next prime is 81457445099. The reversal of 81457445052 is 25054475418.

81457445052 is a `hidden beast` number, since 8 + 145 + 7 + 4 + 450 + 52 = 666.

It is a tau number, because it is divible by the number of its divisors (18).

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 81457444989 and 81457445007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81457445051) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1131353368 + ... + 1131353439.

Almost surely, 2^81457445052 is an apocalyptic number.

It is an amenable number.

81457445052 is an abundant number, since it is smaller than the sum of its proper divisors (124448874476).

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

81457445052 is a wasteful number, since it uses less digits than its factorization.

81457445052 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2262706817 (or 2262706812 counting only the distinct ones).

The product of its (nonzero) digits is 896000, while the sum is 45.

The spelling of 81457445052 in words is "eighty-one billion, four hundred fifty-seven million, four hundred forty-five thousand, fifty-two".