645125 has 16 divisors (see below), whose sum is σ = 869232. Its totient is φ = 475200.

The previous prime is 645097. The next prime is 645131. The reversal of 645125 is 521546.

It can be written as a sum of positive squares in 8 ways, for example, as 276676 + 368449 = 526^2 + 607^2 .

It is not a de Polignac number, because 645125 - 2⁸ = 644869 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 645125.

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, 1427 + ... + 1823.

It is an arithmetic number, because the mean of its divisors is an integer number (54327).

2⁶⁴⁵¹²⁵ is an apocalyptic number.

645125 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

645125 is a deficient number, since it is larger than the sum of its proper divisors (224107).

645125 is a wasteful number, since it uses less digits than its factorization.

645125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 425 (or 415 counting only the distinct ones).

The product of its digits is 1200, while the sum is 23.

The square root of 645125 is about 803.1967380412. The cubic root of 645125 is about 86.4068070911.

The spelling of 645125 in words is "six hundred forty-five thousand, one hundred twenty-five".