81318830 has 16 divisors (see below), whose sum is σ = 146530080. Its totient is φ = 32492832.

The previous prime is 81318829. The next prime is 81318833. The reversal of 81318830 is 3881318.

It is a super-2 number, since 2×81318830² = 13225504225137800, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81318833) 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, 6887 + ... + 14493.

It is an arithmetic number, because the mean of its divisors is an integer number (9158130).

Almost surely, 2^81318830 is an apocalyptic number.

81318830 is a deficient number, since it is larger than the sum of its proper divisors (65211250).

81318830 is a wasteful number, since it uses less digits than its factorization.

81318830 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8683.

The product of its (nonzero) digits is 4608, while the sum is 32.

The square root of 81318830 is about 9017.6953818589. The cubic root of 81318830 is about 433.2418222277.

It can be divided in two parts, 8131 and 8830, that added together give a palindrome (16961).

The spelling of 81318830 in words is "eighty-one million, three hundred eighteen thousand, eight hundred thirty".