81882481 has 2 divisors, whose sum is σ = 81882482. Its totient is φ = 81882480.

The previous prime is 81882433. The next prime is 81882487. The reversal of 81882481 is 18428818.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 68807025 + 13075456 = 8295^2 + 3616^2 .

It is a cyclic number.

It is not a de Polignac number, because 81882481 - 2¹¹ = 81880433 is a prime.

It is a super-2 number, since 2×81882481² = 13409481389430722, which contains 22 as substring.

It is equal to p_4772929 and since 81882481 and 4772929 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (81882487) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40941240 + 40941241.

It is an arithmetic number, because the mean of its divisors is an integer number (40941241).

Almost surely, 2^81882481 is an apocalyptic number.

It is an amenable number.

81882481 is a deficient number, since it is larger than the sum of its proper divisors (1).

81882481 is an equidigital number, since it uses as much as digits as its factorization.

81882481 is an evil number, because the sum of its binary digits is even.

The product of its digits is 32768, while the sum is 40.

The square root of 81882481 is about 9048.8939103075. The cubic root of 81882481 is about 434.2405049922.

The spelling of 81882481 in words is "eighty-one million, eight hundred eighty-two thousand, four hundred eighty-one".