71811828 has 72 divisors (see below), whose sum is σ = 202902336. Its totient is φ = 21225600.

The previous prime is 71811827. The next prime is 71811829. The reversal of 71811828 is 82811817.

It is an interprime number because it is at equal distance from previous prime (71811827) and next prime (71811829).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 71811792 and 71811801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71811821) 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 23 ways as a sum of consecutive naturals, for example, 14025 + ... + 18447.

It is an arithmetic number, because the mean of its divisors is an integer number (2818088).

Almost surely, 2^71811828 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 71811828, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (101451168).

71811828 is an abundant number, since it is smaller than the sum of its proper divisors (131090508).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

71811828 is a wasteful number, since it uses less digits than its factorization.

71811828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4485 (or 4480 counting only the distinct ones).

The product of its digits is 7168, while the sum is 36.

The square root of 71811828 is about 8474.1859786059. The cubic root of 71811828 is about 415.6540284849.

It can be divided in two parts, 7181 and 1828, that added together give a palindrome (9009).

The spelling of 71811828 in words is "seventy-one million, eight hundred eleven thousand, eight hundred twenty-eight".