81318430 has 32 divisors (see below), whose sum is σ = 151305408. Its totient is φ = 31449600.

The previous prime is 81318421. The next prime is 81318439. The reversal of 81318430 is 3481318.

It is an interprime number because it is at equal distance from previous prime (81318421) and next prime (81318439).

It is a super-2 number, since 2×81318430² = 13225374115329800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81318439) 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 15 ways as a sum of consecutive naturals, for example, 36550 + ... + 38710.

It is an arithmetic number, because the mean of its divisors is an integer number (4728294).

Almost surely, 2^81318430 is an apocalyptic number.

81318430 is a deficient number, since it is larger than the sum of its proper divisors (69986978).

81318430 is a wasteful number, since it uses less digits than its factorization.

81318430 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2292.

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 81318430 is about 9017.6732032160. The cubic root of 81318430 is about 433.2411118674.

Adding to 81318430 its reverse (3481318), we get a palindrome (84799748).

It can be divided in two parts, 8131 and 8430, that added together give a palindrome (16561).

The spelling of 81318430 in words is "eighty-one million, three hundred eighteen thousand, four hundred thirty".