81418311 has 16 divisors (see below), whose sum is σ = 129898720. Its totient is φ = 50103360.

The previous prime is 81418301. The next prime is 81418339. The reversal of 81418311 is 11381418.

It is not a de Polignac number, because 81418311 - 2⁵ = 81418279 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81418301) 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, 115630 + ... + 116331.

It is an arithmetic number, because the mean of its divisors is an integer number (8118670).

Almost surely, 2^81418311 is an apocalyptic number.

81418311 is a deficient number, since it is larger than the sum of its proper divisors (48480409).

81418311 is a wasteful number, since it uses less digits than its factorization.

81418311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 231983 (or 231977 counting only the distinct ones).

The product of its digits is 768, while the sum is 27.

The square root of 81418311 is about 9023.2095730954. The cubic root of 81418311 is about 433.4184183352.

Adding to 81418311 its reverse (11381418), we get a palindrome (92799729).

The spelling of 81418311 in words is "eighty-one million, four hundred eighteen thousand, three hundred eleven".