665531445 has 16 divisors (see below), whose sum is σ = 1071387072. Its totient is φ = 352771200.

The previous prime is 665531431. The next prime is 665531459. The reversal of 665531445 is 544135566.

It is an interprime number because it is at equal distance from previous prime (665531431) and next prime (665531459).

It is not a de Polignac number, because 665531445 - 2⁴ = 665531429 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 133656 + ... + 138545.

It is an arithmetic number, because the mean of its divisors is an integer number (66961692).

Almost surely, 2^665531445 is an apocalyptic number.

It is an amenable number.

665531445 is a deficient number, since it is larger than the sum of its proper divisors (405855627).

665531445 is a wasteful number, since it uses less digits than its factorization.

665531445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 272372.

The product of its digits is 216000, while the sum is 39.

The square root of 665531445 is about 25797.8961351502. The cubic root of 665531445 is about 873.0843292822.

The spelling of 665531445 in words is "six hundred sixty-five million, five hundred thirty-one thousand, four hundred forty-five".