628776864 has 96 divisors (see below), whose sum is σ = 1838592000. Its totient is φ = 209060352.

The previous prime is 628776859. The next prime is 628776881. The reversal of 628776864 is 468677826.

628776864 is a `hidden beast` number, since 628 + 7 + 7 + 6 + 8 + 6 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 628776864.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 490977 + ... + 492255.

It is an arithmetic number, because the mean of its divisors is an integer number (19152000).

Almost surely, 2^628776864 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 628776864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (919296000).

628776864 is an abundant number, since it is smaller than the sum of its proper divisors (1209815136).

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

628776864 is a wasteful number, since it uses less digits than its factorization.

628776864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1867 (or 1853 counting only the distinct ones).

The product of its digits is 5419008, while the sum is 54.

The square root of 628776864 is about 25075.4235058952. The cubic root of 628776864 is about 856.7067415699.

The spelling of 628776864 in words is "six hundred twenty-eight million, seven hundred seventy-six thousand, eight hundred sixty-four".