205991072 has 48 divisors (see below), whose sum is σ = 472252032. Its totient is φ = 86611200.

The previous prime is 205991021. The next prime is 205991117. The reversal of 205991072 is 270199502.

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, 3197 + ... + 20547.

It is an arithmetic number, because the mean of its divisors is an integer number (9838584).

Almost surely, 2^205991072 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 205991072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (236126016).

205991072 is an abundant number, since it is smaller than the sum of its proper divisors (266260960).

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

205991072 is a wasteful number, since it uses less digits than its factorization.

205991072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17421 (or 17413 counting only the distinct ones).

The product of its (nonzero) digits is 11340, while the sum is 35.

The square root of 205991072 is about 14352.3890694198. The cubic root of 205991072 is about 590.5855261619.

The spelling of 205991072 in words is "two hundred five million, nine hundred ninety-one thousand, seventy-two".