628405687 has 16 divisors (see below), whose sum is σ = 774011392. Its totient is φ = 496821600.

The previous prime is 628405633. The next prime is 628405691. The reversal of 628405687 is 786504826.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-628405687 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (628405607) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 230788 + ... + 233494.

It is an arithmetic number, because the mean of its divisors is an integer number (48375712).

Almost surely, 2^628405687 is an apocalyptic number.

628405687 is a deficient number, since it is larger than the sum of its proper divisors (145605705).

628405687 is a wasteful number, since it uses less digits than its factorization.

628405687 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5278.

The product of its (nonzero) digits is 645120, while the sum is 46.

The square root of 628405687 is about 25068.0212023207. The cubic root of 628405687 is about 856.5381325087.

The spelling of 628405687 in words is "six hundred twenty-eight million, four hundred five thousand, six hundred eighty-seven".