81182312 has 16 divisors (see below), whose sum is σ = 152412900. Its totient is φ = 40538880.

The previous prime is 81182303. The next prime is 81182333. The reversal of 81182312 is 21328118.

It can be written as a sum of positive squares in 2 ways, for example, as 80532676 + 649636 = 8974^2 + 806^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 512 + ... + 12752.

Almost surely, 2^81182312 is an apocalyptic number.

It is an amenable number.

81182312 is a deficient number, since it is larger than the sum of its proper divisors (71230588).

81182312 is a wasteful number, since it uses less digits than its factorization.

81182312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13076 (or 13072 counting only the distinct ones).

The product of its digits is 768, while the sum is 26.

The square root of 81182312 is about 9010.1227516610. The cubic root of 81182312 is about 432.9992443988. Note that the first 3 decimals are identical.

The spelling of 81182312 in words is "eighty-one million, one hundred eighty-two thousand, three hundred twelve".