645336617 has 4 divisors (see below), whose sum is σ = 645835476. Its totient is φ = 644837760.

The previous prime is 645336613. The next prime is 645336619. The reversal of 645336617 is 716633546.

645336617 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 420906256 + 224430361 = 20516^2 + 14981^2 .

It is a cyclic number.

It is not a de Polignac number, because 645336617 - 2² = 645336613 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (645336613) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 247484 + ... + 250077.

It is an arithmetic number, because the mean of its divisors is an integer number (161458869).

Almost surely, 2^645336617 is an apocalyptic number.

It is an amenable number.

645336617 is a deficient number, since it is larger than the sum of its proper divisors (498859).

645336617 is a wasteful number, since it uses less digits than its factorization.

645336617 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 498858.

The product of its digits is 272160, while the sum is 41.

The square root of 645336617 is about 25403.4764746875. The cubic root of 645336617 is about 864.1625391686.

The spelling of 645336617 in words is "six hundred forty-five million, three hundred thirty-six thousand, six hundred seventeen".