82222221 has 16 divisors (see below), whose sum is σ = 113932800. Its totient is φ = 52680768.

The previous prime is 82222219. The next prime is 82222237. The reversal of 82222221 is 12222228.

It is not a de Polignac number, because 82222221 - 2¹ = 82222219 is a prime.

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82222241) 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, 17860 + ... + 21986.

It is an arithmetic number, because the mean of its divisors is an integer number (7120800).

Almost surely, 2^82222221 is an apocalyptic number.

It is an amenable number.

82222221 is a deficient number, since it is larger than the sum of its proper divisors (31710579).

82222221 is a wasteful number, since it uses less digits than its factorization.

82222221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4388.

The product of its digits is 512, while the sum is 21.

The square root of 82222221 is about 9067.6469384290. The cubic root of 82222221 is about 434.8402478522.

Adding to 82222221 its reverse (12222228), we get a palindrome (94444449).

The spelling of 82222221 in words is "eighty-two million, two hundred twenty-two thousand, two hundred twenty-one".