81455317 has 8 divisors (see below), whose sum is σ = 82869696. Its totient is φ = 80046912.

The previous prime is 81455303. The next prime is 81455323. The reversal of 81455317 is 71355418.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81455317 - 2¹¹ = 81453269 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81455417) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32493 + ... + 34909.

It is an arithmetic number, because the mean of its divisors is an integer number (10358712).

Almost surely, 2^81455317 is an apocalyptic number.

It is an amenable number.

81455317 is a deficient number, since it is larger than the sum of its proper divisors (1414379).

81455317 is a wasteful number, since it uses less digits than its factorization.

81455317 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2987.

The product of its digits is 16800, while the sum is 34.

The square root of 81455317 is about 9025.2599408549. The cubic root of 81455317 is about 433.4840737240.

The spelling of 81455317 in words is "eighty-one million, four hundred fifty-five thousand, three hundred seventeen".