205657991996 has 24 divisors (see below), whose sum is σ = 369850464480. Its totient is φ = 99989767872.

The previous prime is 205657991993. The next prime is 205657991999. The reversal of 205657991996 is 699199756502.

It is an interprime number because it is at equal distance from previous prime (205657991993) and next prime (205657991999).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205657991993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 169280 + ... + 663303.

It is an arithmetic number, because the mean of its divisors is an integer number (15410436020).

Almost surely, 2^205657991996 is an apocalyptic number.

It is an amenable number.

205657991996 is a deficient number, since it is larger than the sum of its proper divisors (164192472484).

205657991996 is a wasteful number, since it uses less digits than its factorization.

205657991996 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 834293 (or 834291 counting only the distinct ones).

The product of its (nonzero) digits is 82668600, while the sum is 68.

The spelling of 205657991996 in words is "two hundred five billion, six hundred fifty-seven million, nine hundred ninety-one thousand, nine hundred ninety-six".