205978120 has 32 divisors (see below), whose sum is σ = 490714200. Its totient is φ = 77544448.

The previous prime is 205978109. The next prime is 205978139. The reversal of 205978120 is 21879502.

It can be written as a sum of positive squares in 4 ways, for example, as 166564836 + 39413284 = 12906^2 + 6278^2 .

It is a Harshad number since it is a multiple of its sum of digits (34).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 150775 + ... + 152134.

Almost surely, 2^205978120 is an apocalyptic number.

205978120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

205978120 is an abundant number, since it is smaller than the sum of its proper divisors (284736080).

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

205978120 is a wasteful number, since it uses less digits than its factorization.

205978120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 302937 (or 302933 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 34.

The square root of 205978120 is about 14351.9378482489. The cubic root of 205978120 is about 590.5731479166.

The spelling of 205978120 in words is "two hundred five million, nine hundred seventy-eight thousand, one hundred twenty".