81157338360 has 576 divisors, whose sum is σ = 327167493120. Its totient is φ = 17080381440.

The previous prime is 81157338341. The next prime is 81157338389. The reversal of 81157338360 is 6383375118.

81157338360 is a `hidden beast` number, since 8 + 11 + 573 + 3 + 8 + 3 + 60 = 666.

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 143 ways as a sum of consecutive naturals, for example, 34227975 + ... + 34230345.

It is an arithmetic number, because the mean of its divisors is an integer number (567999120).

Almost surely, 2^81157338360 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 81157338360, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (163583746560).

81157338360 is an abundant number, since it is smaller than the sum of its proper divisors (246010154760).

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

81157338360 is a wasteful number, since it uses less digits than its factorization.

81157338360 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2476 (or 2452 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 45.

The spelling of 81157338360 in words is "eighty-one billion, one hundred fifty-seven million, three hundred thirty-eight thousand, three hundred sixty".