628638566 has 4 divisors (see below), whose sum is σ = 942957852. Its totient is φ = 314319282.

The previous prime is 628638533. The next prime is 628638581. The reversal of 628638566 is 665836826.

It is a happy number.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 157159640 + ... + 157159643.

It is an arithmetic number, because the mean of its divisors is an integer number (235739463).

Almost surely, 2^628638566 is an apocalyptic number.

628638566 is a deficient number, since it is larger than the sum of its proper divisors (314319286).

628638566 is a wasteful number, since it uses less digits than its factorization.

628638566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 314319285.

The product of its digits is 2488320, while the sum is 50.

The square root of 628638566 is about 25072.6657138805. The cubic root of 628638566 is about 856.6439267500.

The spelling of 628638566 in words is "six hundred twenty-eight million, six hundred thirty-eight thousand, five hundred sixty-six".