8221631 has 4 divisors (see below), whose sum is σ = 8969064. Its totient is φ = 7474200.

The previous prime is 8221627. The next prime is 8221651. The reversal of 8221631 is 1361228.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 8221631 - 2² = 8221627 is a prime.

It is a super-2 number, since 2×8221631² = 135190432600322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 8221597 and 8221606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8221621) 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, 373700 + ... + 373721.

It is an arithmetic number, because the mean of its divisors is an integer number (2242266).

Almost surely, 2^8221631 is an apocalyptic number.

8221631 is a deficient number, since it is larger than the sum of its proper divisors (747433).

8221631 is a wasteful number, since it uses less digits than its factorization.

8221631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 747432.

The product of its digits is 576, while the sum is 23.

The square root of 8221631 is about 2867.3386615466. The cubic root of 8221631 is about 201.8301270928.

Adding to 8221631 its reverse (1361228), we get a palindrome (9582859).

The spelling of 8221631 in words is "eight million, two hundred twenty-one thousand, six hundred thirty-one".