81506207524896 has 1728 divisors, whose sum is σ = 310666022424576. Its totient is φ = 20782224691200.

The previous prime is 81506207524873. The next prime is 81506207524897. The reversal of 81506207524896 is 69842570260518.

81506207524896 is a `hidden beast` number, since 8 + 1 + 5 + 0 + 6 + 20 + 7 + 524 + 89 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (81506207524897) by changing a digit.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 82915775221 + ... + 82915776203.

It is an arithmetic number, because the mean of its divisors is an integer number (179783577792).

Almost surely, 2^{81506207524896} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81506207524896, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (155333011212288).

81506207524896 is an abundant number, since it is smaller than the sum of its proper divisors (229159814899680).

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

81506207524896 is a wasteful number, since it uses less digits than its factorization.

81506207524896 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1377 (or 1350 counting only the distinct ones).

The product of its (nonzero) digits is 58060800, while the sum is 63.

The spelling of 81506207524896 in words is "eighty-one trillion, five hundred six billion, two hundred seven million, five hundred twenty-four thousand, eight hundred ninety-six".