205688340 has 288 divisors, whose sum is σ = 750701952. Its totient is φ = 44928000.

The previous prime is 205688323. The next prime is 205688411. The reversal of 205688340 is 43886502.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 205688295 and 205688304.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1570075 + ... + 1570205.

It is an arithmetic number, because the mean of its divisors is an integer number (2606604).

Almost surely, 2^205688340 is an apocalyptic number.

205688340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 205688340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (375350976).

205688340 is an abundant number, since it is smaller than the sum of its proper divisors (545013612).

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

205688340 is a wasteful number, since it uses less digits than its factorization.

205688340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 231 (or 226 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 36.

The square root of 205688340 is about 14341.8387942411. The cubic root of 205688340 is about 590.2960689662.

The spelling of 205688340 in words is "two hundred five million, six hundred eighty-eight thousand, three hundred forty".