81235321 has 2 divisors, whose sum is σ = 81235322. Its totient is φ = 81235320.

The previous prime is 81235303. The next prime is 81235339. The reversal of 81235321 is 12353218.

It is a balanced prime because it is at equal distance from previous prime (81235303) and next prime (81235339).

It can be written as a sum of positive squares in only one way, i.e., 69538921 + 11696400 = 8339^2 + 3420^2 .

It is a cyclic number.

It is not a de Polignac number, because 81235321 - 2¹⁷ = 81104249 is a prime.

It is not a weakly prime, because it can be changed into another prime (81235421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40617660 + 40617661.

It is an arithmetic number, because the mean of its divisors is an integer number (40617661).

Almost surely, 2^81235321 is an apocalyptic number.

It is an amenable number.

81235321 is a deficient number, since it is larger than the sum of its proper divisors (1).

81235321 is an equidigital number, since it uses as much as digits as its factorization.

81235321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1440, while the sum is 25.

The square root of 81235321 is about 9013.0639074623. The cubic root of 81235321 is about 433.0934679737.

Adding to 81235321 its reverse (12353218), we get a palindrome (93588539).

The spelling of 81235321 in words is "eighty-one million, two hundred thirty-five thousand, three hundred twenty-one".