81362031 has 4 divisors (see below), whose sum is σ = 108482712. Its totient is φ = 54241352.

The previous prime is 81362027. The next prime is 81362033. The reversal of 81362031 is 13026318.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81362031 - 2² = 81362027 is a prime.

It is a super-2 number, since 2×81362031² = 13239560176889922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 81361992 and 81362010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81362033) 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 3 ways as a sum of consecutive naturals, for example, 13560336 + ... + 13560341.

It is an arithmetic number, because the mean of its divisors is an integer number (27120678).

Almost surely, 2^81362031 is an apocalyptic number.

81362031 is a deficient number, since it is larger than the sum of its proper divisors (27120681).

81362031 is a wasteful number, since it uses less digits than its factorization.

81362031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27120680.

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 81362031 is about 9020.0904097465. The cubic root of 81362031 is about 433.3185292115.

Adding to 81362031 its reverse (13026318), we get a palindrome (94388349).

The spelling of 81362031 in words is "eighty-one million, three hundred sixty-two thousand, thirty-one".