628531969 has 8 divisors (see below), whose sum is σ = 677780712. Its totient is φ = 579411840.

The previous prime is 628531961. The next prime is 628531997. The reversal of 628531969 is 969135826.

It can be written as a sum of positive squares in 4 ways, for example, as 7924225 + 620607744 = 2815^2 + 24912^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 628531969 - 2³ = 628531961 is a prime.

It is a super-2 number, since 2×628531969² = 790104872110033922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (628531961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21874 + ... + 41659.

It is an arithmetic number, because the mean of its divisors is an integer number (84722589).

Almost surely, 2^628531969 is an apocalyptic number.

It is an amenable number.

628531969 is a deficient number, since it is larger than the sum of its proper divisors (49248743).

628531969 is a wasteful number, since it uses less digits than its factorization.

628531969 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64307.

The product of its digits is 699840, while the sum is 49.

The square root of 628531969 is about 25070.5398625558. The cubic root of 628531969 is about 856.5955042067.

The spelling of 628531969 in words is "six hundred twenty-eight million, five hundred thirty-one thousand, nine hundred sixty-nine".