81106973 has 4 divisors (see below), whose sum is σ = 81177408. Its totient is φ = 81036540.

The previous prime is 81106937. The next prime is 81107011. The reversal of 81106973 is 37960118.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 81106973 - 2¹⁴ = 81090589 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81106273) 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 3 ways as a sum of consecutive naturals, for example, 33461 + ... + 35802.

It is an arithmetic number, because the mean of its divisors is an integer number (20294352).

Almost surely, 2^81106973 is an apocalyptic number.

It is an amenable number.

81106973 is a deficient number, since it is larger than the sum of its proper divisors (70435).

81106973 is a wasteful number, since it uses less digits than its factorization.

81106973 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70434.

The product of its (nonzero) digits is 9072, while the sum is 35.

The square root of 81106973 is about 9005.9409835952. The cubic root of 81106973 is about 432.8652586175.

The spelling of 81106973 in words is "eighty-one million, one hundred six thousand, nine hundred seventy-three".