205618839551 has 2 divisors, whose sum is σ = 205618839552. Its totient is φ = 205618839550.

The previous prime is 205618839469. The next prime is 205618839563. The reversal of 205618839551 is 155938816502.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-205618839551 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 205618839493 and 205618839502.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205618839451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102809419775 + 102809419776.

It is an arithmetic number, because the mean of its divisors is an integer number (102809419776).

Almost surely, 2^205618839551 is an apocalyptic number.

205618839551 is a deficient number, since it is larger than the sum of its proper divisors (1).

205618839551 is an equidigital number, since it uses as much as digits as its factorization.

205618839551 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2592000, while the sum is 53.

The spelling of 205618839551 in words is "two hundred five billion, six hundred eighteen million, eight hundred thirty-nine thousand, five hundred fifty-one".