81341761 has 2 divisors, whose sum is σ = 81341762. Its totient is φ = 81341760.

The previous prime is 81341759. The next prime is 81341791. The reversal of 81341761 is 16714318.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 51036736 + 30305025 = 7144^2 + 5505^2 .

It is a cyclic number.

It is not a de Polignac number, because 81341761 - 2¹ = 81341759 is a prime.

It is a super-2 number, since 2×81341761² = 13232964165162242, which contains 22 as substring.

Together with 81341759, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (81341791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40670880 + 40670881.

It is an arithmetic number, because the mean of its divisors is an integer number (40670881).

Almost surely, 2^81341761 is an apocalyptic number.

It is an amenable number.

81341761 is a deficient number, since it is larger than the sum of its proper divisors (1).

81341761 is an equidigital number, since it uses as much as digits as its factorization.

81341761 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4032, while the sum is 31.

The square root of 81341761 is about 9018.9667368275. The cubic root of 81341761 is about 433.2825415156.

The spelling of 81341761 in words is "eighty-one million, three hundred forty-one thousand, seven hundred sixty-one".