71243540 has 48 divisors (see below), whose sum is σ = 160876800. Its totient is φ = 26416512.

The previous prime is 71243539. The next prime is 71243563. The reversal of 71243540 is 4534217.

It is a congruent number.

It is an unprimeable number.

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, 15866 + ... + 19854.

It is an arithmetic number, because the mean of its divisors is an integer number (3351600).

Almost surely, 2^71243540 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 71243540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (80438400).

71243540 is an abundant number, since it is smaller than the sum of its proper divisors (89633260).

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

71243540 is a wasteful number, since it uses less digits than its factorization.

71243540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4064 (or 4062 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 26.

The square root of 71243540 is about 8440.5888420181. The cubic root of 71243540 is about 414.5546875712.

Adding to 71243540 its reverse (4534217), we get a palindrome (75777757).

The spelling of 71243540 in words is "seventy-one million, two hundred forty-three thousand, five hundred forty".