81603624960 has 1280 divisors, whose sum is σ = 351699606720. Its totient is φ = 17836277760.

The previous prime is 81603624953. The next prime is 81603625073. The reversal of 81603624960 is 6942630618.

81603624960 is a `hidden beast` number, since 8 + 16 + 0 + 3 + 624 + 9 + 6 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1280).

It is a super-2 number, since 2×81603624960² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 1897758699 + ... + 1897758741.

Almost surely, 2^81603624960 is an apocalyptic number.

81603624960 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81603624960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (175849803360).

81603624960 is an abundant number, since it is smaller than the sum of its proper divisors (270095981760).

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

81603624960 is a wasteful number, since it uses less digits than its factorization.

81603624960 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 114 (or 77 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 45.

The spelling of 81603624960 in words is "eighty-one billion, six hundred three million, six hundred twenty-four thousand, nine hundred sixty".