210396661 has 2 divisors, whose sum is σ = 210396662. Its totient is φ = 210396660.

The previous prime is 210396647. The next prime is 210396733. The reversal of 210396661 is 166693012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 195720100 + 14676561 = 13990^2 + 3831^2 .

It is a cyclic number.

It is not a de Polignac number, because 210396661 - 2⁵ = 210396629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (210396601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105198330 + 105198331.

It is an arithmetic number, because the mean of its divisors is an integer number (105198331).

Almost surely, 2^210396661 is an apocalyptic number.

It is an amenable number.

210396661 is a deficient number, since it is larger than the sum of its proper divisors (1).

210396661 is an equidigital number, since it uses as much as digits as its factorization.

210396661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11664, while the sum is 34.

The square root of 210396661 is about 14505.0563942371. The cubic root of 210396661 is about 594.7662014844.

The spelling of 210396661 in words is "two hundred ten million, three hundred ninety-six thousand, six hundred sixty-one".