205626661 has 2 divisors, whose sum is σ = 205626662. Its totient is φ = 205626660.

The previous prime is 205626653. The next prime is 205626671. The reversal of 205626661 is 166626502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 205033761 + 592900 = 14319^2 + 770^2 .

It is a cyclic number.

It is not a de Polignac number, because 205626661 - 2³ = 205626653 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205626671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102813330 + 102813331.

It is an arithmetic number, because the mean of its divisors is an integer number (102813331).

Almost surely, 2^205626661 is an apocalyptic number.

It is an amenable number.

205626661 is a deficient number, since it is larger than the sum of its proper divisors (1).

205626661 is an equidigital number, since it uses as much as digits as its factorization.

205626661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25920, while the sum is 34.

The square root of 205626661 is about 14339.6883159991. The cubic root of 205626661 is about 590.2370597696.

The spelling of 205626661 in words is "two hundred five million, six hundred twenty-six thousand, six hundred sixty-one".