81338177 has 4 divisors (see below), whose sum is σ = 81371136. Its totient is φ = 81305220.

The previous prime is 81338171. The next prime is 81338207. The reversal of 81338177 is 77183318.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 81338177 - 2⁴ = 81338161 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81338177.

It is not an unprimeable number, because it can be changed into a prime (81338171) 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, 12449 + ... + 17822.

It is an arithmetic number, because the mean of its divisors is an integer number (20342784).

Almost surely, 2^81338177 is an apocalyptic number.

It is an amenable number.

81338177 is a deficient number, since it is larger than the sum of its proper divisors (32959).

81338177 is a wasteful number, since it uses less digits than its factorization.

81338177 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32958.

The product of its digits is 28224, while the sum is 38.

The square root of 81338177 is about 9018.7680422550. The cubic root of 81338177 is about 433.2761778003.

The spelling of 81338177 in words is "eighty-one million, three hundred thirty-eight thousand, one hundred seventy-seven".