645739237 has 32 divisors (see below), whose sum is σ = 838252800. Its totient is φ = 487787520.

The previous prime is 645739231. The next prime is 645739261. The reversal of 645739237 is 732937546.

It is not a de Polignac number, because 645739237 - 2⁷ = 645739109 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645739231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 50139 + ... + 61687.

It is an arithmetic number, because the mean of its divisors is an integer number (26195400).

Almost surely, 2^645739237 is an apocalyptic number.

It is an amenable number.

645739237 is a deficient number, since it is larger than the sum of its proper divisors (192513563).

645739237 is a wasteful number, since it uses less digits than its factorization.

645739237 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11613.

The product of its digits is 952560, while the sum is 46.

The square root of 645739237 is about 25411.3997449963. The cubic root of 645739237 is about 864.3422163484.

The spelling of 645739237 in words is "six hundred forty-five million, seven hundred thirty-nine thousand, two hundred thirty-seven".