205185471988 has 18 divisors (see below), whose sum is σ = 417698996946. Its totient is φ = 87936630768.

The previous prime is 205185471913. The next prime is 205185471991. The reversal of 205185471988 is 889174581502.

It can be written as a sum of positive squares in only one way, i.e., 148894113424 + 56291358564 = 385868^2 + 237258^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 523432131 + ... + 523432522.

Almost surely, 2^205185471988 is an apocalyptic number.

205185471988 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

205185471988 is an abundant number, since it is smaller than the sum of its proper divisors (212513524958).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

205185471988 is a wasteful number, since it uses less digits than its factorization.

205185471988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1046864671 (or 1046864662 counting only the distinct ones).

The product of its (nonzero) digits is 6451200, while the sum is 58.

The spelling of 205185471988 in words is "two hundred five billion, one hundred eighty-five million, four hundred seventy-one thousand, nine hundred eighty-eight".