81359471 has 8 divisors (see below), whose sum is σ = 84319920. Its totient is φ = 78409408.

The previous prime is 81359461. The next prime is 81359477. The reversal of 81359471 is 17495318.

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 81359471 - 2²² = 77165167 is a prime.

It is a super-3 number, since 3×81359471³ (a number of 25 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81359477) 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, 15620 + ... + 20166.

It is an arithmetic number, because the mean of its divisors is an integer number (10539990).

Almost surely, 2^81359471 is an apocalyptic number.

81359471 is a deficient number, since it is larger than the sum of its proper divisors (2960449).

81359471 is a wasteful number, since it uses less digits than its factorization.

81359471 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5193.

The product of its digits is 30240, while the sum is 38.

The square root of 81359471 is about 9019.9485031789. The cubic root of 81359471 is about 433.3139844747.

The spelling of 81359471 in words is "eighty-one million, three hundred fifty-nine thousand, four hundred seventy-one".