206725621 has 2 divisors, whose sum is σ = 206725622. Its totient is φ = 206725620.

The previous prime is 206725579. The next prime is 206725637. The reversal of 206725621 is 126527602.

206725621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 194044900 + 12680721 = 13930^2 + 3561^2 .

It is a cyclic number.

It is not a de Polignac number, because 206725621 - 2¹³ = 206717429 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (206725691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103362810 + 103362811.

It is an arithmetic number, because the mean of its divisors is an integer number (103362811).

Almost surely, 2^206725621 is an apocalyptic number.

It is an amenable number.

206725621 is a deficient number, since it is larger than the sum of its proper divisors (1).

206725621 is an equidigital number, since it uses as much as digits as its factorization.

206725621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10080, while the sum is 31.

The square root of 206725621 is about 14377.9560786643. The cubic root of 206725621 is about 591.2866882284.

The spelling of 206725621 in words is "two hundred six million, seven hundred twenty-five thousand, six hundred twenty-one".