628573991 has 4 divisors (see below), whose sum is σ = 629663952. Its totient is φ = 627484032.

The previous prime is 628573987. The next prime is 628574003. The reversal of 628573991 is 199375826.

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

It is a cyclic number.

It is not a de Polignac number, because 628573991 - 2² = 628573987 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (628573901) 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 3 ways as a sum of consecutive naturals, for example, 544115 + ... + 545268.

It is an arithmetic number, because the mean of its divisors is an integer number (157415988).

Almost surely, 2^628573991 is an apocalyptic number.

628573991 is a deficient number, since it is larger than the sum of its proper divisors (1089961).

628573991 is a wasteful number, since it uses less digits than its factorization.

628573991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1089960.

The product of its digits is 816480, while the sum is 50.

The square root of 628573991 is about 25071.3779238398. The cubic root of 628573991 is about 856.6145936913.

The spelling of 628573991 in words is "six hundred twenty-eight million, five hundred seventy-three thousand, nine hundred ninety-one".