665605450 has 12 divisors (see below), whose sum is σ = 1238026230. Its totient is φ = 266242160.

The previous prime is 665605427. The next prime is 665605483. The reversal of 665605450 is 54506566.

665605450 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 3 ways, for example, as 342361009 + 323244441 = 18503^2 + 17979^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6656005 + ... + 6656104.

Almost surely, 2^665605450 is an apocalyptic number.

665605450 is a deficient number, since it is larger than the sum of its proper divisors (572420780).

665605450 is a wasteful number, since it uses less digits than its factorization.

665605450 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13312121 (or 13312116 counting only the distinct ones).

The product of its (nonzero) digits is 108000, while the sum is 37.

The square root of 665605450 is about 25799.3304176678. The cubic root of 665605450 is about 873.1166894917.

It can be divided in two parts, 66560 and 5450, that added together give a triangular number (72010 = T₃₇₉).

The spelling of 665605450 in words is "six hundred sixty-five million, six hundred five thousand, four hundred fifty".