81010331 has 2 divisors, whose sum is σ = 81010332. Its totient is φ = 81010330.

The previous prime is 81010327. The next prime is 81010339. The reversal of 81010331 is 13301018.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81010331 - 2² = 81010327 is a prime.

It is a super-2 number, since 2×81010331² = 13125347457459122, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (81010339) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40505165 + 40505166.

It is an arithmetic number, because the mean of its divisors is an integer number (40505166).

Almost surely, 2^81010331 is an apocalyptic number.

81010331 is a deficient number, since it is larger than the sum of its proper divisors (1).

81010331 is an equidigital number, since it uses as much as digits as its factorization.

81010331 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72, while the sum is 17.

The square root of 81010331 is about 9000.5739261449. The cubic root of 81010331 is about 432.6932652242.

Adding to 81010331 its reverse (13301018), we get a palindrome (94311349).

The spelling of 81010331 in words is "eighty-one million, ten thousand, three hundred thirty-one".