81408671 has 8 divisors (see below), whose sum is σ = 82879488. Its totient is φ = 79947000.

The previous prime is 81408643. The next prime is 81408737. The reversal of 81408671 is 17680418.

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 81408671 - 2¹⁴ = 81392287 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 (81408601) 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, 17126 + ... + 21356.

It is an arithmetic number, because the mean of its divisors is an integer number (10359936).

Almost surely, 2^81408671 is an apocalyptic number.

81408671 is a deficient number, since it is larger than the sum of its proper divisors (1470817).

81408671 is a wasteful number, since it uses less digits than its factorization.

81408671 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4573.

The product of its (nonzero) digits is 10752, while the sum is 35.

The square root of 81408671 is about 9022.6753792875. The cubic root of 81408671 is about 433.4013119521.

The spelling of 81408671 in words is "eighty-one million, four hundred eight thousand, six hundred seventy-one".