628421787 has 16 divisors (see below), whose sum is σ = 1063994880. Its totient is φ = 359098056.

The previous prime is 628421777. The next prime is 628421869. The reversal of 628421787 is 787124826.

628421787 is a `hidden beast` number, since 628 + 4 + 2 + 17 + 8 + 7 = 666.

It is not a de Polignac number, because 628421787 - 2⁴ = 628421771 is a prime.

It is not an unprimeable number, because it can be changed into a prime (628421707) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1662303 + ... + 1662680.

It is an arithmetic number, because the mean of its divisors is an integer number (66499680).

Almost surely, 2^628421787 is an apocalyptic number.

628421787 is a deficient number, since it is larger than the sum of its proper divisors (435573093).

628421787 is a wasteful number, since it uses less digits than its factorization.

628421787 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3324999 (or 3324993 counting only the distinct ones).

The product of its digits is 301056, while the sum is 45.

The square root of 628421787 is about 25068.3423265281. The cubic root of 628421787 is about 856.5454473938.

The spelling of 628421787 in words is "six hundred twenty-eight million, four hundred twenty-one thousand, seven hundred eighty-seven".