628638565 has 8 divisors (see below), whose sum is σ = 768599928. Its totient is φ = 493421760.

The previous prime is 628638533. The next prime is 628638581. The reversal of 628638565 is 565836826.

It can be written as a sum of positive squares in 4 ways, for example, as 178944129 + 449694436 = 13377^2 + 21206^2 .

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

It is not a de Polignac number, because 628638565 - 2⁵ = 628638533 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1185846 + ... + 1186375.

It is an arithmetic number, because the mean of its divisors is an integer number (96074991).

Almost surely, 2^628638565 is an apocalyptic number.

It is an amenable number.

628638565 is a deficient number, since it is larger than the sum of its proper divisors (139961363).

628638565 is a wasteful number, since it uses less digits than its factorization.

628638565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2372279.

The product of its digits is 2073600, while the sum is 49.

The square root of 628638565 is about 25072.6656939385. The cubic root of 628638565 is about 856.6439262957.

The spelling of 628638565 in words is "six hundred twenty-eight million, six hundred thirty-eight thousand, five hundred sixty-five".