71811144 has 64 divisors (see below), whose sum is σ = 200304000. Its totient is φ = 23837760.

The previous prime is 71811133. The next prime is 71811149. The reversal of 71811144 is 44111817.

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

It is not an unprimeable number, because it can be changed into a prime (71811149) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 66642 + ... + 67710.

It is an arithmetic number, because the mean of its divisors is an integer number (3129750).

Almost surely, 2^71811144 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 71811144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (100152000).

71811144 is an abundant number, since it is smaller than the sum of its proper divisors (128492856).

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

71811144 is a wasteful number, since it uses less digits than its factorization.

71811144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1395 (or 1385 counting only the distinct ones).

The product of its digits is 896, while the sum is 27.

The square root of 71811144 is about 8474.1456206511. The cubic root of 71811144 is about 415.6527087939.

The spelling of 71811144 in words is "seventy-one million, eight hundred eleven thousand, one hundred forty-four".