71390440 has 32 divisors (see below), whose sum is σ = 175232160. Its totient is φ = 25960000.

The previous prime is 71390401. The next prime is 71390441. The reversal of 71390440 is 4409317.

It is a junction number, because it is equal to n+sod(n) for n = 71390399 and 71390408.

It is not an unprimeable number, because it can be changed into a prime (71390441) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 80686 + ... + 81565.

It is an arithmetic number, because the mean of its divisors is an integer number (5476005).

Almost surely, 2^71390440 is an apocalyptic number.

It is an amenable number.

71390440 is an abundant number, since it is smaller than the sum of its proper divisors (103841720).

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

71390440 is a wasteful number, since it uses less digits than its factorization.

71390440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162273 (or 162269 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 28.

The square root of 71390440 is about 8449.2863603975. The cubic root of 71390440 is about 414.8394211082.

Adding to 71390440 its reverse (4409317), we get a palindrome (75799757).

The spelling of 71390440 in words is "seventy-one million, three hundred ninety thousand, four hundred forty".