628878564 has 36 divisors (see below), whose sum is σ = 1590563520. Its totient is φ = 209507760.

The previous prime is 628878557. The next prime is 628878589. The reversal of 628878564 is 465878826.

628878564 is a `hidden beast` number, since 6 + 2 + 8 + 8 + 78 + 564 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a self number, because there is not a number n which added to its sum of digits gives 628878564.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 79417 + ... + 86975.

It is an arithmetic number, because the mean of its divisors is an integer number (44182320).

Almost surely, 2^628878564 is an apocalyptic number.

It is an amenable number.

628878564 is an abundant number, since it is smaller than the sum of its proper divisors (961684956).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

628878564 is a wasteful number, since it uses less digits than its factorization.

628878564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9880 (or 9875 counting only the distinct ones).

The product of its digits is 5160960, while the sum is 54.

The square root of 628878564 is about 25077.4513059043. The cubic root of 628878564 is about 856.7529277364.

The spelling of 628878564 in words is "six hundred twenty-eight million, eight hundred seventy-eight thousand, five hundred sixty-four".