205491380 has 24 divisors (see below), whose sum is σ = 433708800. Its totient is φ = 81781920.

The previous prime is 205491353. The next prime is 205491383. The reversal of 205491380 is 83194502.

205491380 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205491383) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21836 + ... + 29795.

It is an arithmetic number, because the mean of its divisors is an integer number (18071200).

Almost surely, 2^205491380 is an apocalyptic number.

205491380 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

205491380 is an abundant number, since it is smaller than the sum of its proper divisors (228217420).

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

205491380 is a wasteful number, since it uses less digits than its factorization.

205491380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51839 (or 51837 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 32.

The square root of 205491380 is about 14334.9705266526. The cubic root of 205491380 is about 590.1075931329.

The spelling of 205491380 in words is "two hundred five million, four hundred ninety-one thousand, three hundred eighty".