206874821 has 2 divisors, whose sum is σ = 206874822. Its totient is φ = 206874820.

The previous prime is 206874803. The next prime is 206874823. The reversal of 206874821 is 128478602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 151536100 + 55338721 = 12310^2 + 7439^2 .

It is a cyclic number.

It is not a de Polignac number, because 206874821 - 2¹⁴ = 206858437 is a prime.

Together with 206874823, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (206874823) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103437410 + 103437411.

It is an arithmetic number, because the mean of its divisors is an integer number (103437411).

Almost surely, 2^206874821 is an apocalyptic number.

It is an amenable number.

206874821 is a deficient number, since it is larger than the sum of its proper divisors (1).

206874821 is an equidigital number, since it uses as much as digits as its factorization.

206874821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 43008, while the sum is 38.

The square root of 206874821 is about 14383.1436410821. The cubic root of 206874821 is about 591.4289037221.

The spelling of 206874821 in words is "two hundred six million, eight hundred seventy-four thousand, eight hundred twenty-one".