628811709 has 8 divisors (see below), whose sum is σ = 840508032. Its totient is φ = 418161600.

The previous prime is 628811699. The next prime is 628811723. The reversal of 628811709 is 907118826.

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

It is a de Polignac number, because none of the positive numbers 2^k-628811709 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (628811749) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 260149 + ... + 262554.

It is an arithmetic number, because the mean of its divisors is an integer number (105063504).

Almost surely, 2^628811709 is an apocalyptic number.

It is an amenable number.

628811709 is a deficient number, since it is larger than the sum of its proper divisors (211696323).

628811709 is a wasteful number, since it uses less digits than its factorization.

628811709 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 523107.

The product of its (nonzero) digits is 48384, while the sum is 42.

The square root of 628811709 is about 25076.1183000878. The cubic root of 628811709 is about 856.7225666831.

The spelling of 628811709 in words is "six hundred twenty-eight million, eight hundred eleven thousand, seven hundred nine".