645337 has 24 divisors (see below), whose sum is σ = 884160. Its totient is φ = 456960.

The previous prime is 645329. The next prime is 645347. The reversal of 645337 is 733546.

645337 is nontrivially palindromic in base 16.

It is not a de Polignac number, because 645337 - 2³ = 645329 is a prime.

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (645347) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 22239 + ... + 22267.

It is an arithmetic number, because the mean of its divisors is an integer number (36840).

2⁶⁴⁵³³⁷ is an apocalyptic number.

It is an amenable number.

645337 is a deficient number, since it is larger than the sum of its proper divisors (238823).

645337 is a wasteful number, since it uses less digits than its factorization.

645337 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81 (or 64 counting only the distinct ones).

The product of its digits is 7560, while the sum is 28.

The square root of 645337 is about 803.3286998483. The cubic root of 645337 is about 86.4162710126.

Subtracting 645337 from its reverse (733546), we obtain a square (88209 = 297²).

The spelling of 645337 in words is "six hundred forty-five thousand, three hundred thirty-seven".