210102220021 has 2 divisors, whose sum is σ = 210102220022. Its totient is φ = 210102220020.

The previous prime is 210102219941. The next prime is 210102220033. The reversal of 210102220021 is 120022201012.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 194423674225 + 15678545796 = 440935^2 + 125214^2 .

It is a cyclic number.

It is not a de Polignac number, because 210102220021 - 2³⁵ = 175742481653 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 210102219983 and 210102220010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (210102220421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105051110010 + 105051110011.

It is an arithmetic number, because the mean of its divisors is an integer number (105051110011).

Almost surely, 2^210102220021 is an apocalyptic number.

It is an amenable number.

210102220021 is a deficient number, since it is larger than the sum of its proper divisors (1).

210102220021 is an equidigital number, since it uses as much as digits as its factorization.

210102220021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 210102220021 its reverse (120022201012), we get a palindrome (330124421033).

The spelling of 210102220021 in words is "two hundred ten billion, one hundred two million, two hundred twenty thousand, twenty-one".