81132311 has 8 divisors (see below), whose sum is σ = 88356240. Its totient is φ = 74048832.

The previous prime is 81132281. The next prime is 81132319. The reversal of 81132311 is 11323118.

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

It is a de Polignac number, because none of the positive numbers 2^k-81132311 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 (81132319) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33905 + ... + 36218.

It is an arithmetic number, because the mean of its divisors is an integer number (11044530).

Almost surely, 2^81132311 is an apocalyptic number.

81132311 is a deficient number, since it is larger than the sum of its proper divisors (7223929).

81132311 is a wasteful number, since it uses less digits than its factorization.

81132311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70225.

The product of its digits is 144, while the sum is 20.

The square root of 81132311 is about 9007.3476118111. The cubic root of 81132311 is about 432.9103299497.

Adding to 81132311 its reverse (11323118), we get a palindrome (92455429).

The spelling of 81132311 in words is "eighty-one million, one hundred thirty-two thousand, three hundred eleven".