645507 has 12 divisors (see below), whose sum is σ = 987480. Its totient is φ = 404928.

The previous prime is 645503. The next prime is 645521. The reversal of 645507 is 705546.

645507 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 645507 - 2² = 645503 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

645507 is a lucky number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 645507.

It is not an unprimeable number, because it can be changed into a prime (645503) 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, 1957 + ... + 2262.

It is an arithmetic number, because the mean of its divisors is an integer number (82290).

2⁶⁴⁵⁵⁰⁷ is an apocalyptic number.

645507 is a deficient number, since it is larger than the sum of its proper divisors (341973).

645507 is a wasteful number, since it uses less digits than its factorization.

645507 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4242 (or 4239 counting only the distinct ones).

The product of its (nonzero) digits is 4200, while the sum is 27.

The square root of 645507 is about 803.4345026198. The cubic root of 645507 is about 86.4238585088.

The spelling of 645507 in words is "six hundred forty-five thousand, five hundred seven".