81845045 has 8 divisors (see below), whose sum is σ = 99559896. Its totient is φ = 64578816.

The previous prime is 81845041. The next prime is 81845051. The reversal of 81845045 is 54054818.

It can be written as a sum of positive squares in 4 ways, for example, as 538756 + 81306289 = 734^2 + 9017^2 .

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 81845045 - 2² = 81845041 is a prime.

It is a super-2 number, since 2×81845045² = 13397222782104050, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 81844996 and 81845014.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81845041) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 111752 + ... + 112481.

It is an arithmetic number, because the mean of its divisors is an integer number (12444987).

Almost surely, 2^81845045 is an apocalyptic number.

It is an amenable number.

81845045 is a deficient number, since it is larger than the sum of its proper divisors (17714851).

81845045 is a wasteful number, since it uses less digits than its factorization.

81845045 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 224311.

The product of its (nonzero) digits is 25600, while the sum is 35.

The square root of 81845045 is about 9046.8251337140. The cubic root of 81845045 is about 434.1743178365.

The spelling of 81845045 in words is "eighty-one million, eight hundred forty-five thousand, forty-five".