81135054 has 256 divisors, whose sum is σ = 258048000. Its totient is φ = 18195840.

The previous prime is 81135049. The next prime is 81135079. The reversal of 81135054 is 45053118.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 1026987 + ... + 1027065.

It is an arithmetic number, because the mean of its divisors is an integer number (1008000).

Almost surely, 2^81135054 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81135054, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (129024000).

81135054 is an abundant number, since it is smaller than the sum of its proper divisors (176912946).

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

81135054 is a wasteful number, since it uses less digits than its factorization.

81135054 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140 (or 134 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 27.

The square root of 81135054 is about 9007.4998751041. The cubic root of 81135054 is about 432.9152086458.

The spelling of 81135054 in words is "eighty-one million, one hundred thirty-five thousand, fifty-four".