645351 has 16 divisors (see below), whose sum is σ = 998400. Its totient is φ = 363168.

The previous prime is 645347. The next prime is 645353. The reversal of 645351 is 153546.

It is not a de Polignac number, because 645351 - 2² = 645347 is a prime.

It is an Ulam number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 645351.

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 15 ways as a sum of consecutive naturals, for example, 1465 + ... + 1853.

It is an arithmetic number, because the mean of its divisors is an integer number (62400).

2⁶⁴⁵³⁵¹ is an apocalyptic number.

645351 is a deficient number, since it is larger than the sum of its proper divisors (353049).

645351 is a wasteful number, since it uses less digits than its factorization.

645351 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 478.

The product of its digits is 1800, while the sum is 24.

The square root of 645351 is about 803.3374135443. The cubic root of 645351 is about 86.4168959155.

Adding to 645351 its reverse (153546), we get a palindrome (798897).

The spelling of 645351 in words is "six hundred forty-five thousand, three hundred fifty-one".