1668210101 has 2 divisors, whose sum is σ = 1668210102. Its totient is φ = 1668210100.

The previous prime is 1668210077. The next prime is 1668210121. The reversal of 1668210101 is 1010128661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1443240100 + 224970001 = 37990^2 + 14999^2 .

It is a cyclic number.

It is not a de Polignac number, because 1668210101 - 2¹⁰ = 1668209077 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1668210121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 834105050 + 834105051.

It is an arithmetic number, because the mean of its divisors is an integer number (834105051).

Almost surely, 2^1668210101 is an apocalyptic number.

It is an amenable number.

1668210101 is a deficient number, since it is larger than the sum of its proper divisors (1).

1668210101 is an equidigital number, since it uses as much as digits as its factorization.

1668210101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 26.

The square root of 1668210101 is about 40843.7278048907. The cubic root of 1668210101 is about 1185.9969773286.

Adding to 1668210101 its reverse (1010128661), we get a palindrome (2678338762).

The spelling of 1668210101 in words is "one billion, six hundred sixty-eight million, two hundred ten thousand, one hundred one".