645355 has 8 divisors (see below), whose sum is σ = 778752. Its totient is φ = 513408.

The previous prime is 645353. The next prime is 645367. The reversal of 645355 is 553546.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 645355 - 2¹ = 645353 is a prime.

It is a Duffinian number.

645355 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (645353) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1494 + ... + 1876.

It is an arithmetic number, because the mean of its divisors is an integer number (97344).

2⁶⁴⁵³⁵⁵ is an apocalyptic number.

645355 is a deficient number, since it is larger than the sum of its proper divisors (133397).

645355 is a wasteful number, since it uses less digits than its factorization.

645355 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 725.

The product of its digits is 9000, while the sum is 28.

The square root of 645355 is about 803.3399031543. The cubic root of 645355 is about 86.4170744576.

Subtracting from 645355 its reverse (553546), we obtain a square (91809 = 303²).

It can be divided in two parts, 645 and 355, that added together give a cube (1000 = 10³).

The spelling of 645355 in words is "six hundred forty-five thousand, three hundred fifty-five".