81058182409 has 4 divisors (see below), whose sum is σ = 85826310804. Its totient is φ = 76290054016.

The previous prime is 81058182391. The next prime is 81058182427. The reversal of 81058182409 is 90428185018.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (81058182391) and next prime (81058182427).

It can be written as a sum of positive squares in 2 ways, for example, as 73549440000 + 7508742409 = 271200^2 + 86653^2 .

It is a cyclic number.

It is not a de Polignac number, because 81058182409 - 2⁷ = 81058182281 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81058182479) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2384064172 + ... + 2384064205.

It is an arithmetic number, because the mean of its divisors is an integer number (21456577701).

Almost surely, 2^81058182409 is an apocalyptic number.

It is an amenable number.

81058182409 is a deficient number, since it is larger than the sum of its proper divisors (4768128395).

81058182409 is a wasteful number, since it uses less digits than its factorization.

81058182409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4768128394.

The product of its (nonzero) digits is 184320, while the sum is 46.

The spelling of 81058182409 in words is "eighty-one billion, fifty-eight million, one hundred eighty-two thousand, four hundred nine".