501222121 has 2 divisors, whose sum is σ = 501222122. Its totient is φ = 501222120.

The previous prime is 501222119. The next prime is 501222191. The reversal of 501222121 is 121222105.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 486820096 + 14402025 = 22064^2 + 3795^2 .

It is a cyclic number.

It is not a de Polignac number, because 501222121 - 2¹ = 501222119 is a prime.

It is a super-2 number, since 2×501222121² = 502447229159477282, which contains 22 as substring.

Together with 501222119, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 501222095 and 501222104.

It is not a weakly prime, because it can be changed into another prime (501222191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 250611060 + 250611061.

It is an arithmetic number, because the mean of its divisors is an integer number (250611061).

Almost surely, 2^501222121 is an apocalyptic number.

It is an amenable number.

501222121 is a deficient number, since it is larger than the sum of its proper divisors (1).

501222121 is an equidigital number, since it uses as much as digits as its factorization.

501222121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 80, while the sum is 16.

The square root of 501222121 is about 22387.9905529728. The cubic root of 501222121 is about 794.3466652165.

Subtracting from 501222121 its sum of digits (16), we obtain a palindrome (501222105).

Adding to 501222121 its reverse (121222105), we get a palindrome (622444226).

The spelling of 501222121 in words is "five hundred one million, two hundred twenty-two thousand, one hundred twenty-one".