205667680 has 48 divisors (see below), whose sum is σ = 489207600. Its totient is φ = 81705472.

The previous prime is 205667677. The next prime is 205667701. The reversal of 205667680 is 86766502.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19527 + ... + 28153.

It is an arithmetic number, because the mean of its divisors is an integer number (10191825).

Almost surely, 2^205667680 is an apocalyptic number.

205667680 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 205667680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (244603800).

205667680 is an abundant number, since it is smaller than the sum of its proper divisors (283539920).

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

205667680 is a wasteful number, since it uses less digits than its factorization.

205667680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8791 (or 8783 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 40.

The square root of 205667680 is about 14341.1185058907. The cubic root of 205667680 is about 590.2763045577.

The spelling of 205667680 in words is "two hundred five million, six hundred sixty-seven thousand, six hundred eighty".