665005445 has 16 divisors (see below), whose sum is σ = 880355952. Its totient is φ = 479101440.

The previous prime is 665005441. The next prime is 665005447. The reversal of 665005445 is 544500566.

665005445 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 8 ways, for example, as 250842244 + 414163201 = 15838^2 + 20351^2 .

It is not a de Polignac number, because 665005445 - 2² = 665005441 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665005441) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 122102 + ... + 127431.

It is an arithmetic number, because the mean of its divisors is an integer number (55022247).

Almost surely, 2^665005445 is an apocalyptic number.

665005445 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

665005445 is a deficient number, since it is larger than the sum of its proper divisors (215350507).

665005445 is a wasteful number, since it uses less digits than its factorization.

665005445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 249592.

The product of its (nonzero) digits is 72000, while the sum is 35.

The square root of 665005445 is about 25787.6994902609. The cubic root of 665005445 is about 872.8542558071.

The spelling of 665005445 in words is "six hundred sixty-five million, five thousand, four hundred forty-five".