81845051 has 2 divisors, whose sum is σ = 81845052. Its totient is φ = 81845050.

The previous prime is 81845041. The next prime is 81845069. The reversal of 81845051 is 15054818.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81845051 - 2²⁶ = 14736187 is a prime.

It is a super-2 number, since 2×81845051² = 13397224746385202, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 81844999 and 81845017.

It is not a weakly prime, because it can be changed into another prime (81845041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40922525 + 40922526.

It is an arithmetic number, because the mean of its divisors is an integer number (40922526).

Almost surely, 2^81845051 is an apocalyptic number.

81845051 is a deficient number, since it is larger than the sum of its proper divisors (1).

81845051 is an equidigital number, since it uses as much as digits as its factorization.

81845051 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6400, while the sum is 32.

The square root of 81845051 is about 9046.8254653221. The cubic root of 81845051 is about 434.1743284461.

Adding to 81845051 its reverse (15054818), we get a palindrome (96899869).

The spelling of 81845051 in words is "eighty-one million, eight hundred forty-five thousand, fifty-one".