81058577 has 4 divisors (see below), whose sum is σ = 81360180. Its totient is φ = 80756976.

The previous prime is 81058573. The next prime is 81058633. The reversal of 81058577 is 77585018.

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

It can be written as a sum of positive squares in 2 ways, for example, as 38142976 + 42915601 = 6176^2 + 6551^2 .

It is a cyclic number.

It is not a de Polignac number, because 81058577 - 2² = 81058573 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81058573) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 150398 + ... + 150935.

It is an arithmetic number, because the mean of its divisors is an integer number (20340045).

Almost surely, 2^81058577 is an apocalyptic number.

It is an amenable number.

81058577 is a deficient number, since it is larger than the sum of its proper divisors (301603).

81058577 is a wasteful number, since it uses less digits than its factorization.

81058577 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 301602.

The product of its (nonzero) digits is 78400, while the sum is 41.

The square root of 81058577 is about 9003.2536896391. The cubic root of 81058577 is about 432.7791455318.

The spelling of 81058577 in words is "eighty-one million, fifty-eight thousand, five hundred seventy-seven".