81105929 has 8 divisors (see below), whose sum is σ = 86728968. Its totient is φ = 75577600.

The previous prime is 81105917. The next prime is 81105931. The reversal of 81105929 is 92950118.

It can be written as a sum of positive squares in 4 ways, for example, as 17935225 + 63170704 = 4235^2 + 7948^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81105929 - 2¹² = 81101833 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81105029) 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 7 ways as a sum of consecutive naturals, for example, 21902 + ... + 25335.

It is an arithmetic number, because the mean of its divisors is an integer number (10841121).

Almost surely, 2^81105929 is an apocalyptic number.

It is an amenable number.

81105929 is a deficient number, since it is larger than the sum of its proper divisors (5623039).

81105929 is a wasteful number, since it uses less digits than its factorization.

81105929 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47355.

The product of its (nonzero) digits is 6480, while the sum is 35.

The square root of 81105929 is about 9005.8830216698. The cubic root of 81105929 is about 432.8634013449.

The spelling of 81105929 in words is "eighty-one million, one hundred five thousand, nine hundred twenty-nine".