205309555220 has 96 divisors (see below), whose sum is σ = 569157684480. Its totient is φ = 60228311040.

The previous prime is 205309555219. The next prime is 205309555313. The reversal of 205309555220 is 22555903502.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3894935 + ... + 3947294.

It is an arithmetic number, because the mean of its divisors is an integer number (5928725880).

Almost surely, 2^205309555220 is an apocalyptic number.

205309555220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

205309555220 is an abundant number, since it is smaller than the sum of its proper divisors (363848129260).

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

205309555220 is a wasteful number, since it uses less digits than its factorization.

205309555220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7842273 (or 7842271 counting only the distinct ones).

The product of its (nonzero) digits is 135000, while the sum is 38.

The spelling of 205309555220 in words is "two hundred five billion, three hundred nine million, five hundred fifty-five thousand, two hundred twenty".