205564816 has 40 divisors (see below), whose sum is σ = 432019224. Its totient is φ = 94371840.

The previous prime is 205564787. The next prime is 205564817. The reversal of 205564816 is 618465502.

It can be written as a sum of positive squares in 4 ways, for example, as 16777216 + 188787600 = 4096^2 + 13740^2 .

It is a super-2 number, since 2×205564816² = 84513787154227712, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (205564817) 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, 1936 + ... + 20368.

Almost surely, 2^205564816 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 205564816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (216009612).

205564816 is an abundant number, since it is smaller than the sum of its proper divisors (226454408).

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

205564816 is a wasteful number, since it uses less digits than its factorization.

205564816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18499 (or 18493 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 37.

The square root of 205564816 is about 14337.5317262073. The cubic root of 205564816 is about 590.1778799094.

The spelling of 205564816 in words is "two hundred five million, five hundred sixty-four thousand, eight hundred sixteen".