81266142873600 has 1728 divisors, whose sum is σ = 312545495808000. Its totient is φ = 20119692902400.

The previous prime is 81266142873523. The next prime is 81266142873611. The reversal of 81266142873600 is 637824166218.

It is a happy number.

81266142873600 is a `hidden beast` number, since 8 + 1 + 2 + 6 + 6 + 1 + 4 + 28 + 7 + 3 + 600 = 666.

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, 148566988527 + ... + 148566989073.

It is an arithmetic number, because the mean of its divisors is an integer number (180871236000).

Almost surely, 2^{81266142873600} is an apocalyptic number.

81266142873600 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 81266142873600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (156272747904000).

81266142873600 is an abundant number, since it is smaller than the sum of its proper divisors (231279352934400).

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

81266142873600 is a wasteful number, since it uses less digits than its factorization.

81266142873600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 914 (or 886 counting only the distinct ones).

The product of its (nonzero) digits is 4644864, while the sum is 54.

The spelling of 81266142873600 in words is "eighty-one trillion, two hundred sixty-six billion, one hundred forty-two million, eight hundred seventy-three thousand, six hundred".