81103320 has 48 divisors (see below), whose sum is σ = 263586960. Its totient is φ = 21627456.

The previous prime is 81103307. The next prime is 81103331. The reversal of 81103320 is 2330118.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 81103293 and 81103302.

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 11 ways as a sum of consecutive naturals, for example, 112284 + ... + 113003.

It is an arithmetic number, because the mean of its divisors is an integer number (5491395).

Almost surely, 2^81103320 is an apocalyptic number.

It is an amenable number.

81103320 is an abundant number, since it is smaller than the sum of its proper divisors (182483640).

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

81103320 is a wasteful number, since it uses less digits than its factorization.

81103320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 225304 (or 225297 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 81103320 is about 9005.7381707443. The cubic root of 81103320 is about 432.8587598728.

Adding to 81103320 its reverse (2330118), we get a palindrome (83433438).

The spelling of 81103320 in words is "eighty-one million, one hundred three thousand, three hundred twenty".