205520551 has 2 divisors, whose sum is σ = 205520552. Its totient is φ = 205520550.

The previous prime is 205520537. The next prime is 205520603. The reversal of 205520551 is 155025502.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-205520551 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205520501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102760275 + 102760276.

It is an arithmetic number, because the mean of its divisors is an integer number (102760276).

Almost surely, 2^205520551 is an apocalyptic number.

205520551 is a deficient number, since it is larger than the sum of its proper divisors (1).

205520551 is an equidigital number, since it uses as much as digits as its factorization.

205520551 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2500, while the sum is 25.

The square root of 205520551 is about 14335.9879673499. The cubic root of 205520551 is about 590.1355151705.

The spelling of 205520551 in words is "two hundred five million, five hundred twenty thousand, five hundred fifty-one".