210129217 has 2 divisors, whose sum is σ = 210129218. Its totient is φ = 210129216.

The previous prime is 210129137. The next prime is 210129229. The reversal of 210129217 is 712921012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 197233936 + 12895281 = 14044^2 + 3591^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-210129217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 210129191 and 210129200.

It is not a weakly prime, because it can be changed into another prime (210129277) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105064608 + 105064609.

It is an arithmetic number, because the mean of its divisors is an integer number (105064609).

Almost surely, 2^210129217 is an apocalyptic number.

It is an amenable number.

210129217 is a deficient number, since it is larger than the sum of its proper divisors (1).

210129217 is an equidigital number, since it uses as much as digits as its factorization.

210129217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 504, while the sum is 25.

The square root of 210129217 is about 14495.8344706333. The cubic root of 210129217 is about 594.5140838928.

The spelling of 210129217 in words is "two hundred ten million, one hundred twenty-nine thousand, two hundred seventeen".