81534156 has 72 divisors (see below), whose sum is σ = 210882672. Its totient is φ = 24499200.

The previous prime is 81534151. The next prime is 81534157. The reversal of 81534156 is 65143518.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (81534151) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 338196 + ... + 338436.

It is an arithmetic number, because the mean of its divisors is an integer number (2928926).

Almost surely, 2^81534156 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 81534156, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (105441336).

81534156 is an abundant number, since it is smaller than the sum of its proper divisors (129348516).

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

81534156 is a wasteful number, since it uses less digits than its factorization.

81534156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 503 (or 490 counting only the distinct ones).

The product of its digits is 14400, while the sum is 33.

The square root of 81534156 is about 9029.6265703516. The cubic root of 81534156 is about 433.6238821988.

The spelling of 81534156 in words is "eighty-one million, five hundred thirty-four thousand, one hundred fifty-six".