81341213 has 2 divisors, whose sum is σ = 81341214. Its totient is φ = 81341212.

The previous prime is 81341203. The next prime is 81341231. The reversal of 81341213 is 31214318.

Together with next prime (81341231) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 76510009 + 4831204 = 8747^2 + 2198^2 .

It is a cyclic number.

It is not a de Polignac number, because 81341213 - 2¹² = 81337117 is a prime.

It is a super-2 number, since 2×81341213² = 13232785864622738, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81341203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40670606 + 40670607.

It is an arithmetic number, because the mean of its divisors is an integer number (40670607).

Almost surely, 2^81341213 is an apocalyptic number.

It is an amenable number.

81341213 is a deficient number, since it is larger than the sum of its proper divisors (1).

81341213 is an equidigital number, since it uses as much as digits as its factorization.

81341213 is an evil number, because the sum of its binary digits is even.

The product of its digits is 576, while the sum is 23.

The square root of 81341213 is about 9018.9363563560. The cubic root of 81341213 is about 433.2815685043.

The spelling of 81341213 in words is "eighty-one million, three hundred forty-one thousand, two hundred thirteen".