81541893162240 has 1440 divisors, whose sum is σ = 359732955859200. Its totient is φ = 17210670317568.

The previous prime is 81541893162161. The next prime is 81541893162241. The reversal of 81541893162240 is 4226139814518.

81541893162240 is a `hidden beast` number, since 8 + 1 + 5 + 4 + 1 + 8 + 9 + 3 + 1 + 622 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1440).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81541893162241) by changing a digit.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 653847411 + ... + 653972109.

It is an arithmetic number, because the mean of its divisors is an integer number (249814552680).

Almost surely, 2^{81541893162240} is an apocalyptic number.

81541893162240 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 81541893162240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (179866477929600).

81541893162240 is an abundant number, since it is smaller than the sum of its proper divisors (278191062696960).

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

81541893162240 is a wasteful number, since it uses less digits than its factorization.

81541893162240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 124809 (or 124786 counting only the distinct ones).

The product of its (nonzero) digits is 3317760, while the sum is 54.

The spelling of 81541893162240 in words is "eighty-one trillion, five hundred forty-one billion, eight hundred ninety-three million, one hundred sixty-two thousand, two hundred forty".