81327631 has 8 divisors (see below), whose sum is σ = 101395584. Its totient is φ = 63372120.

The previous prime is 81327611. The next prime is 81327647. The reversal of 81327631 is 13672318.

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

It is not a de Polignac number, because 81327631 - 2⁷ = 81327503 is a prime.

It is a super-2 number, since 2×81327631² = 13228367128144322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81327593 and 81327602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81327611) 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, 528025 + ... + 528178.

It is an arithmetic number, because the mean of its divisors is an integer number (12674448).

Almost surely, 2^81327631 is an apocalyptic number.

81327631 is a deficient number, since it is larger than the sum of its proper divisors (20067953).

81327631 is a wasteful number, since it uses less digits than its factorization.

81327631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1056221.

The product of its digits is 6048, while the sum is 31.

The square root of 81327631 is about 9018.1833536472. The cubic root of 81327631 is about 433.2574513414.

Adding to 81327631 its reverse (13672318), we get a palindrome (94999949).

The spelling of 81327631 in words is "eighty-one million, three hundred twenty-seven thousand, six hundred thirty-one".