205115641 has 2 divisors, whose sum is σ = 205115642. Its totient is φ = 205115640.

The previous prime is 205115639. The next prime is 205115657. The reversal of 205115641 is 146511502.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 204604416 + 511225 = 14304^2 + 715^2 .

It is a cyclic number.

It is not a de Polignac number, because 205115641 - 2¹ = 205115639 is a prime.

Together with 205115639, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (205115941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102557820 + 102557821.

It is an arithmetic number, because the mean of its divisors is an integer number (102557821).

Almost surely, 2^205115641 is an apocalyptic number.

It is an amenable number.

205115641 is a deficient number, since it is larger than the sum of its proper divisors (1).

205115641 is an equidigital number, since it uses as much as digits as its factorization.

205115641 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1200, while the sum is 25.

The square root of 205115641 is about 14321.8588528166. The cubic root of 205115641 is about 589.7477050184.

The spelling of 205115641 in words is "two hundred five million, one hundred fifteen thousand, six hundred forty-one".