81137238000 has 1440 divisors, whose sum is σ = 348671112192. Its totient is φ = 16144128000.

The previous prime is 81137237989. The next prime is 81137238047. The reversal of 81137238000 is 83273118.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 1142777965 + ... + 1142778035.

Almost surely, 2^81137238000 is an apocalyptic number.

81137238000 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 81137238000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (174335556096).

81137238000 is an abundant number, since it is smaller than the sum of its proper divisors (267533874192).

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

81137238000 is a wasteful number, since it uses less digits than its factorization.

81137238000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160 (or 124 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 33.

The spelling of 81137238000 in words is "eighty-one billion, one hundred thirty-seven million, two hundred thirty-eight thousand".