205406400 has 84 divisors (see below), whose sum is σ = 673919912. Its totient is φ = 54773760.

The previous prime is 205406293. The next prime is 205406423. The reversal of 205406400 is 4604502.

It is a happy number.

It is a super-3 number, since 3×205406400³ (a number of 26 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16597 + ... + 26196.

Almost surely, 2^205406400 is an apocalyptic number.

205406400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

205406400 is an abundant number, since it is smaller than the sum of its proper divisors (468513512).

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

205406400 is a wasteful number, since it uses less digits than its factorization.

205406400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42818 (or 42803 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 21.

The square root of 205406400 is about 14332.0061401047. The cubic root of 205406400 is about 590.0262365044.

The spelling of 205406400 in words is "two hundred five million, four hundred six thousand, four hundred".