206404621 has 2 divisors, whose sum is σ = 206404622. Its totient is φ = 206404620.

The previous prime is 206404613. The next prime is 206404637. The reversal of 206404621 is 126404602.

206404621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 201952521 + 4452100 = 14211^2 + 2110^2 .

It is a cyclic number.

It is not a de Polignac number, because 206404621 - 2³ = 206404613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (206404661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103202310 + 103202311.

It is an arithmetic number, because the mean of its divisors is an integer number (103202311).

Almost surely, 2^206404621 is an apocalyptic number.

It is an amenable number.

206404621 is a deficient number, since it is larger than the sum of its proper divisors (1).

206404621 is an equidigital number, since it uses as much as digits as its factorization.

206404621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 206404621 is about 14366.7888200530. The cubic root of 206404621 is about 590.9804830730.

It can be divided in two parts, 206404 and 621, that added together give a square (207025 = 455²).

The spelling of 206404621 in words is "two hundred six million, four hundred four thousand, six hundred twenty-one".