210154121 has 2 divisors, whose sum is σ = 210154122. Its totient is φ = 210154120.

The previous prime is 210154111. The next prime is 210154127. The reversal of 210154121 is 121451012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 208369225 + 1784896 = 14435^2 + 1336^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-210154121 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 210154121.

It is not a weakly prime, because it can be changed into another prime (210154127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105077060 + 105077061.

It is an arithmetic number, because the mean of its divisors is an integer number (105077061).

Almost surely, 2^210154121 is an apocalyptic number.

It is an amenable number.

210154121 is a deficient number, since it is larger than the sum of its proper divisors (1).

210154121 is an equidigital number, since it uses as much as digits as its factorization.

210154121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 80, while the sum is 17.

The square root of 210154121 is about 14496.6934505769. The cubic root of 210154121 is about 594.5375697492.

The spelling of 210154121 in words is "two hundred ten million, one hundred fifty-four thousand, one hundred twenty-one".