81083281 has 8 divisors (see below), whose sum is σ = 84065184. Its totient is φ = 78149280.

The previous prime is 81083273. The next prime is 81083297. The reversal of 81083281 is 18238018.

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

It is not a de Polignac number, because 81083281 - 2³ = 81083273 is a prime.

It is a super-2 number, since 2×81083281² = 13148996915449922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81083201) 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, 8511 + ... + 15316.

It is an arithmetic number, because the mean of its divisors is an integer number (10508148).

Almost surely, 2^81083281 is an apocalyptic number.

It is an amenable number.

81083281 is a deficient number, since it is larger than the sum of its proper divisors (2981903).

81083281 is a wasteful number, since it uses less digits than its factorization.

81083281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23951.

The product of its (nonzero) digits is 3072, while the sum is 31.

The square root of 81083281 is about 9004.6255335800. The cubic root of 81083281 is about 432.8231067035.

The spelling of 81083281 in words is "eighty-one million, eighty-three thousand, two hundred eighty-one".