81045861 has 16 divisors (see below), whose sum is σ = 118016640. Its totient is φ = 49170240.

The previous prime is 81045857. The next prime is 81045869. The reversal of 81045861 is 16854018.

It is not a de Polignac number, because 81045861 - 2² = 81045857 is a prime.

It is a nialpdrome in base 14.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81045869) 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 15 ways as a sum of consecutive naturals, for example, 11866 + ... + 17403.

It is an arithmetic number, because the mean of its divisors is an integer number (7376040).

Almost surely, 2^81045861 is an apocalyptic number.

It is an amenable number.

81045861 is a deficient number, since it is larger than the sum of its proper divisors (36970779).

81045861 is a wasteful number, since it uses less digits than its factorization.

81045861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29356.

The product of its (nonzero) digits is 7680, while the sum is 33.

The square root of 81045861 is about 9002.5474727990. The cubic root of 81045861 is about 432.7565137199.

Adding to 81045861 its reverse (16854018), we get a palindrome (97899879).

The spelling of 81045861 in words is "eighty-one million, forty-five thousand, eight hundred sixty-one".