645085 has 12 divisors (see below), whose sum is σ = 900828. Its totient is φ = 442176.

The previous prime is 645083. The next prime is 645091. The reversal of 645085 is 580546.

It can be written as a sum of positive squares in 2 ways, for example, as 164836 + 480249 = 406^2 + 693^2 .

It is not a de Polignac number, because 645085 - 2¹ = 645083 is a prime.

It is a super-2 number, since 2×645085² = 832269314450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645083) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1072 + ... + 1561.

It is an arithmetic number, because the mean of its divisors is an integer number (75069).

2⁶⁴⁵⁰⁸⁵ is an apocalyptic number.

It is an amenable number.

645085 is a deficient number, since it is larger than the sum of its proper divisors (255743).

645085 is a wasteful number, since it uses less digits than its factorization.

645085 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2652 (or 2645 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 28.

The square root of 645085 is about 803.1718371557. The cubic root of 645085 is about 86.4050212131.

The spelling of 645085 in words is "six hundred forty-five thousand, eighty-five".