71449840 has 120 divisors (see below), whose sum is σ = 210937392. Its totient is φ = 22256640.

The previous prime is 71449837. The next prime is 71449841. The reversal of 71449840 is 4894417.

It is a self number, because there is not a number n which added to its sum of digits gives 71449840.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71449841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 42292 + ... + 43948.

Almost surely, 2^71449840 is an apocalyptic number.

71449840 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 71449840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (105468696).

71449840 is an abundant number, since it is smaller than the sum of its proper divisors (139487552).

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

71449840 is a wasteful number, since it uses less digits than its factorization.

71449840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1695 (or 1682 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 37.

The square root of 71449840 is about 8452.8007192883. The cubic root of 71449840 is about 414.9544441212.

The spelling of 71449840 in words is "seventy-one million, four hundred forty-nine thousand, eight hundred forty".