71624221 has 4 divisors (see below), whose sum is σ = 71647200. Its totient is φ = 71601244.

The previous prime is 71624219. The next prime is 71624299. The reversal of 71624221 is 12242617.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 71624221 - 2¹ = 71624219 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71624321) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5911 + ... + 13348.

It is an arithmetic number, because the mean of its divisors is an integer number (17911800).

Almost surely, 2^71624221 is an apocalyptic number.

It is an amenable number.

71624221 is a deficient number, since it is larger than the sum of its proper divisors (22979).

71624221 is a wasteful number, since it uses less digits than its factorization.

71624221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22978.

The product of its digits is 1344, while the sum is 25.

The square root of 71624221 is about 8463.1094167569. The cubic root of 71624221 is about 415.2917501390.

Adding to 71624221 its reverse (12242617), we get a palindrome (83866838).

The spelling of 71624221 in words is "seventy-one million, six hundred twenty-four thousand, two hundred twenty-one".