2002121021 has 2 divisors, whose sum is σ = 2002121022. Its totient is φ = 2002121020.

The previous prime is 2002121003. The next prime is 2002121027. The reversal of 2002121021 is 1201212002.

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., 1004256100 + 997864921 = 31690^2 + 31589^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2002121021 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2002120993 and 2002121011.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2002121027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1001060510 + 1001060511.

It is an arithmetic number, because the mean of its divisors is an integer number (1001060511).

Almost surely, 2^2002121021 is an apocalyptic number.

It is an amenable number.

2002121021 is a deficient number, since it is larger than the sum of its proper divisors (1).

2002121021 is an equidigital number, since it uses as much as digits as its factorization.

2002121021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 2002121021 is about 44745.0670018495. The cubic root of 2002121021 is about 1260.3662790427.

Adding to 2002121021 its reverse (1201212002), we get a palindrome (3203333023).

The spelling of 2002121021 in words is "two billion, two million, one hundred twenty-one thousand, twenty-one".