210042281 has 2 divisors, whose sum is σ = 210042282. Its totient is φ = 210042280.

The previous prime is 210042263. The next prime is 210042341. The reversal of 210042281 is 182240012.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 115777600 + 94264681 = 10760^2 + 9709^2 .

It is a cyclic number.

It is not a de Polignac number, because 210042281 - 2¹⁴ = 210025897 is a prime.

It is a super-2 number, since 2×210042281² = 88235519615365922, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (210042181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105021140 + 105021141.

It is an arithmetic number, because the mean of its divisors is an integer number (105021141).

Almost surely, 2^210042281 is an apocalyptic number.

It is an amenable number.

210042281 is a deficient number, since it is larger than the sum of its proper divisors (1).

210042281 is an equidigital number, since it uses as much as digits as its factorization.

210042281 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 256, while the sum is 20.

The square root of 210042281 is about 14492.8355058629. The cubic root of 210042281 is about 594.4320838635.

Adding to 210042281 its reverse (182240012), we get a palindrome (392282293).

The spelling of 210042281 in words is "two hundred ten million, forty-two thousand, two hundred eighty-one".