205401887 has 2 divisors, whose sum is σ = 205401888. Its totient is φ = 205401886.

The previous prime is 205401883. The next prime is 205401893. The reversal of 205401887 is 788104502.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 205401887 - 2² = 205401883 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205401883) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102700943 + 102700944.

It is an arithmetic number, because the mean of its divisors is an integer number (102700944).

Almost surely, 2^205401887 is an apocalyptic number.

205401887 is a deficient number, since it is larger than the sum of its proper divisors (1).

205401887 is an equidigital number, since it uses as much as digits as its factorization.

205401887 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17920, while the sum is 35.

The square root of 205401887 is about 14331.8486944288. The cubic root of 205401887 is about 590.0219153020.

The spelling of 205401887 in words is "two hundred five million, four hundred one thousand, eight hundred eighty-seven".