205449990 has 16 divisors (see below), whose sum is σ = 493080048. Its totient is φ = 54786656.

The previous prime is 205449973. The next prime is 205449997. The reversal of 205449990 is 99944502.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205449997) 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, 3424137 + ... + 3424196.

It is an arithmetic number, because the mean of its divisors is an integer number (30817503).

Almost surely, 2^205449990 is an apocalyptic number.

205449990 is an abundant number, since it is smaller than the sum of its proper divisors (287630058).

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

205449990 is a wasteful number, since it uses less digits than its factorization.

205449990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6848343.

The product of its (nonzero) digits is 116640, while the sum is 42.

The square root of 205449990 is about 14333.5267816403. The cubic root of 205449990 is about 590.0679707194.

The spelling of 205449990 in words is "two hundred five million, four hundred forty-nine thousand, nine hundred ninety".