81136000 has 128 divisors (see below), whose sum is σ = 220540320. Its totient is φ = 29440000.

The previous prime is 81135983. The next prime is 81136037. The reversal of 81136000 is 63118.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 175770 + ... + 176230.

Almost surely, 2^81136000 is an apocalyptic number.

81136000 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 81136000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (110270160).

81136000 is an abundant number, since it is smaller than the sum of its proper divisors (139404320).

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

81136000 is a wasteful number, since it uses less digits than its factorization.

81136000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 501 (or 479 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 81136000 is about 9007.5523867475. The cubic root of 81136000 is about 432.9168911746.

Adding to 81136000 its reverse (63118), we get a palindrome (81199118).

The spelling of 81136000 in words is "eighty-one million, one hundred thirty-six thousand".