220135021 has 2 divisors, whose sum is σ = 220135022. Its totient is φ = 220135020.

The previous prime is 220134997. The next prime is 220135033. The reversal of 220135021 is 120531022.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 125753796 + 94381225 = 11214^2 + 9715^2 .

It is a cyclic number.

It is not a de Polignac number, because 220135021 - 2¹⁹ = 219610733 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 220134986 and 220135004.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (220135051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 110067510 + 110067511.

It is an arithmetic number, because the mean of its divisors is an integer number (110067511).

Almost surely, 2^220135021 is an apocalyptic number.

It is an amenable number.

220135021 is a deficient number, since it is larger than the sum of its proper divisors (1).

220135021 is an equidigital number, since it uses as much as digits as its factorization.

220135021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 220135021 is about 14836.9478330282. The cubic root of 220135021 is about 603.8045478509.

Adding to 220135021 its reverse (120531022), we get a palindrome (340666043).

The spelling of 220135021 in words is "two hundred twenty million, one hundred thirty-five thousand, twenty-one".