81282231 has 32 divisors (see below), whose sum is σ = 124416000. Its totient is φ = 52419744.

The previous prime is 81282211. The next prime is 81282251. The reversal of 81282231 is 13228218.

It is an interprime number because it is at equal distance from previous prime (81282211) and next prime (81282251).

It is not a de Polignac number, because 81282231 - 2¹⁷ = 81151159 is a prime.

It is a super-2 number, since 2×81282231² = 13213602152674722, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 81282195 and 81282204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81282211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 112690 + ... + 113408.

It is an arithmetic number, because the mean of its divisors is an integer number (3888000).

Almost surely, 2^81282231 is an apocalyptic number.

81282231 is a deficient number, since it is larger than the sum of its proper divisors (43133769).

81282231 is a wasteful number, since it uses less digits than its factorization.

81282231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 860 (or 854 counting only the distinct ones).

The product of its digits is 1536, while the sum is 27.

The square root of 81282231 is about 9015.6658655920. The cubic root of 81282231 is about 433.1768163865.

The spelling of 81282231 in words is "eighty-one million, two hundred eighty-two thousand, two hundred thirty-one".