205671430957 has 2 divisors, whose sum is σ = 205671430958. Its totient is φ = 205671430956.

The previous prime is 205671430933. The next prime is 205671431027. The reversal of 205671430957 is 759034176502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 157915632996 + 47755797961 = 397386^2 + 218531^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-205671430957 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 205671430957.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205671439957) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102835715478 + 102835715479.

It is an arithmetic number, because the mean of its divisors is an integer number (102835715479).

Almost surely, 2^205671430957 is an apocalyptic number.

It is an amenable number.

205671430957 is a deficient number, since it is larger than the sum of its proper divisors (1).

205671430957 is an equidigital number, since it uses as much as digits as its factorization.

205671430957 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1587600, while the sum is 49.

The spelling of 205671430957 in words is "two hundred five billion, six hundred seventy-one million, four hundred thirty thousand, nine hundred fifty-seven".