628931 has 4 divisors (see below), whose sum is σ = 633864. Its totient is φ = 624000.

The previous prime is 628921. The next prime is 628937. The reversal of 628931 is 139826.

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 628931 - 2¹⁸ = 366787 is a prime.

It is a super-2 number, since 2×628931² = 791108405522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 628894 and 628903.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 628931.

It is not an unprimeable number, because it can be changed into a prime (628937) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2270 + ... + 2531.

It is an arithmetic number, because the mean of its divisors is an integer number (158466).

2⁶²⁸⁹³¹ is an apocalyptic number.

628931 is a deficient number, since it is larger than the sum of its proper divisors (4933).

628931 is a wasteful number, since it uses less digits than its factorization.

628931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4932.

The product of its digits is 2592, while the sum is 29.

The square root of 628931 is about 793.0517007106. The cubic root of 628931 is about 85.6776739142.

The spelling of 628931 in words is "six hundred twenty-eight thousand, nine hundred thirty-one".