102002000021 has 2 divisors, whose sum is σ = 102002000022. Its totient is φ = 102002000020.

The previous prime is 102002000017. The next prime is 102002000027. The reversal of 102002000021 is 120000200201.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 51886461796 + 50115538225 = 227786^2 + 223865^2 .

It is a cyclic number.

It is not a de Polignac number, because 102002000021 - 2² = 102002000017 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 102001999972 and 102002000008.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (102002000027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51001000010 + 51001000011.

It is an arithmetic number, because the mean of its divisors is an integer number (51001000011).

Almost surely, 2^102002000021 is an apocalyptic number.

It is an amenable number.

102002000021 is a deficient number, since it is larger than the sum of its proper divisors (1).

102002000021 is an equidigital number, since it uses as much as digits as its factorization.

102002000021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8, while the sum is 8.

Adding to 102002000021 its reverse (120000200201), we get a palindrome (222002200222).

The spelling of 102002000021 in words is "one hundred two billion, two million, twenty-one", and thus it is an aban number.