210140981 has 2 divisors, whose sum is σ = 210140982. Its totient is φ = 210140980.

The previous prime is 210140963. The next prime is 210140999. The reversal of 210140981 is 189041012.

It is a balanced prime because it is at equal distance from previous prime (210140963) and next prime (210140999).

It can be written as a sum of positive squares in only one way, i.e., 206180881 + 3960100 = 14359^2 + 1990^2 .

It is a cyclic number.

It is not a de Polignac number, because 210140981 - 2¹⁰ = 210139957 is a prime.

It is a super-2 number, since 2×210140981² = 88318463791284722, which contains 22 as substring.

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 210140981.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (210140911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105070490 + 105070491.

It is an arithmetic number, because the mean of its divisors is an integer number (105070491).

Almost surely, 2^210140981 is an apocalyptic number.

It is an amenable number.

210140981 is a deficient number, since it is larger than the sum of its proper divisors (1).

210140981 is an equidigital number, since it uses as much as digits as its factorization.

210140981 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 210140981 is about 14496.2402366959. The cubic root of 210140981 is about 594.5251782300.

Adding to 210140981 its reverse (189041012), we get a palindrome (399181993).

The spelling of 210140981 in words is "two hundred ten million, one hundred forty thousand, nine hundred eighty-one".