81451317 has 8 divisors (see below), whose sum is σ = 109006560. Its totient is φ = 54098480.

The previous prime is 81451277. The next prime is 81451327. The reversal of 81451317 is 71315418.

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 81451317 - 2⁷ = 81451189 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81451327) 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, 49659 + ... + 51272.

It is an arithmetic number, because the mean of its divisors is an integer number (13625820).

Almost surely, 2^81451317 is an apocalyptic number.

It is an amenable number.

81451317 is a deficient number, since it is larger than the sum of its proper divisors (27555243).

81451317 is a wasteful number, since it uses less digits than its factorization.

81451317 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101203.

The product of its digits is 3360, while the sum is 30.

The square root of 81451317 is about 9025.0383378687. The cubic root of 81451317 is about 433.4769779536.

The spelling of 81451317 in words is "eighty-one million, four hundred fifty-one thousand, three hundred seventeen".