71240040 has 64 divisors (see below), whose sum is σ = 237470400. Its totient is φ = 18997056.

The previous prime is 71240023. The next prime is 71240041. The reversal of 71240040 is 4004217.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a zygodrome in base 3.

It is a junction number, because it is equal to n+sod(n) for n = 71239995 and 71240022.

It is not an unprimeable number, because it can be changed into a prime (71240041) 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, 31902 + ... + 34061.

It is an arithmetic number, because the mean of its divisors is an integer number (3710475).

Almost surely, 2^71240040 is an apocalyptic number.

It is an amenable number.

71240040 is an abundant number, since it is smaller than the sum of its proper divisors (166230360).

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

71240040 is a wasteful number, since it uses less digits than its factorization.

71240040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65983 (or 65973 counting only the distinct ones).

The product of its (nonzero) digits is 224, while the sum is 18.

The square root of 71240040 is about 8440.3815079651. The cubic root of 71240040 is about 414.5478988146.

Adding to 71240040 its reverse (4004217), we get a palindrome (75244257).

The spelling of 71240040 in words is "seventy-one million, two hundred forty thousand, forty".