81163742063040 has 1344 divisors, whose sum is σ = 361370758275072. Its totient is φ = 16259479142400.

The previous prime is 81163742063029. The next prime is 81163742063069. The reversal of 81163742063040 is 4036024736118.

81163742063040 is a `hidden beast` number, since 8 + 1 + 1 + 6 + 3 + 7 + 4 + 2 + 0 + 630 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1344).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 430503195 + ... + 430691685.

It is an arithmetic number, because the mean of its divisors is an integer number (268877052288).

Almost surely, 2^{81163742063040} is an apocalyptic number.

81163742063040 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 81163742063040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (180685379137536).

81163742063040 is an abundant number, since it is smaller than the sum of its proper divisors (280207016212032).

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

81163742063040 is a wasteful number, since it uses less digits than its factorization.

81163742063040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 188618 (or 188605 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 45.

Adding to 81163742063040 its reverse (4036024736118), we get a palindrome (85199766799158).

The spelling of 81163742063040 in words is "eighty-one trillion, one hundred sixty-three billion, seven hundred forty-two million, sixty-three thousand, forty".