628780669 has 4 divisors (see below), whose sum is σ = 685942560. Its totient is φ = 571618780.

The previous prime is 628780667. The next prime is 628780681. The reversal of 628780669 is 966087826.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 628780669 - 2¹ = 628780667 is a prime.

It is a super-2 number, since 2×628780669² = 790730259416175122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (628780667) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28580929 + ... + 28580950.

It is an arithmetic number, because the mean of its divisors is an integer number (171485640).

Almost surely, 2^628780669 is an apocalyptic number.

It is an amenable number.

628780669 is a deficient number, since it is larger than the sum of its proper divisors (57161891).

628780669 is a wasteful number, since it uses less digits than its factorization.

628780669 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57161890.

The product of its (nonzero) digits is 1741824, while the sum is 52.

The square root of 628780669 is about 25075.4993768818. The cubic root of 628780669 is about 856.7084696671.

The spelling of 628780669 in words is "six hundred twenty-eight million, seven hundred eighty thousand, six hundred sixty-nine".