71222640 has 80 divisors (see below), whose sum is σ = 232425600. Its totient is φ = 17991936.

The previous prime is 71222633. The next prime is 71222647. The reversal of 71222640 is 4622217.

It is an interprime number because it is at equal distance from previous prime (71222633) and next prime (71222647).

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 71222640.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71222647) by changing a digit.

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, 3250 + ... + 12369.

It is an arithmetic number, because the mean of its divisors is an integer number (2905320).

Almost surely, 2^71222640 is an apocalyptic number.

It is an amenable number.

71222640 is an abundant number, since it is smaller than the sum of its proper divisors (161202960).

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

71222640 is a wasteful number, since it uses less digits than its factorization.

71222640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15654 (or 15648 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 24.

The square root of 71222640 is about 8439.3506859237. The cubic root of 71222640 is about 414.5141456950.

Adding to 71222640 its reverse (4622217), we get a palindrome (75844857).

The spelling of 71222640 in words is "seventy-one million, two hundred twenty-two thousand, six hundred forty".