205421550 has 48 divisors (see below), whose sum is σ = 510317040. Its totient is φ = 54685440.

The previous prime is 205421549. The next prime is 205421563. The reversal of 205421550 is 55124502.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 205421550.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 168744 + ... + 169956.

It is an arithmetic number, because the mean of its divisors is an integer number (10631605).

Almost surely, 2^205421550 is an apocalyptic number.

205421550 is an abundant number, since it is smaller than the sum of its proper divisors (304895490).

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

205421550 is a wasteful number, since it uses less digits than its factorization.

205421550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2357 (or 2352 counting only the distinct ones).

The product of its (nonzero) digits is 2000, while the sum is 24.

The square root of 205421550 is about 14332.5346676713. The cubic root of 205421550 is about 590.0407421832.

The spelling of 205421550 in words is "two hundred five million, four hundred twenty-one thousand, five hundred fifty".