81021160 has 64 divisors (see below), whose sum is σ = 202305600. Its totient is φ = 28953600.

The previous prime is 81021137. The next prime is 81021169. The reversal of 81021160 is 6112018.

It is not an unprimeable number, because it can be changed into a prime (81021169) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24400 + ... + 27520.

It is an arithmetic number, because the mean of its divisors is an integer number (3161025).

Almost surely, 2^81021160 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 81021160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (101152800).

81021160 is an abundant number, since it is smaller than the sum of its proper divisors (121284440).

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

81021160 is a wasteful number, since it uses less digits than its factorization.

81021160 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3202 (or 3198 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 19.

The square root of 81021160 is about 9001.1754787916. The cubic root of 81021160 is about 432.7125443562.

Adding to 81021160 its reverse (6112018), we get a palindrome (87133178).

It can be divided in two parts, 810 and 21160, that multiplied together give a square (17139600 = 4140²).

The spelling of 81021160 in words is "eighty-one million, twenty-one thousand, one hundred sixty".