628706131909 has 4 divisors (see below), whose sum is σ = 632925636300. Its totient is φ = 624486627520.

The previous prime is 628706131873. The next prime is 628706131919. The reversal of 628706131909 is 909131607826.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 204143119684 + 424563012225 = 451822^2 + 651585^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-628706131909 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 (628706131919) 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, 2109751972 + ... + 2109752269.

It is an arithmetic number, because the mean of its divisors is an integer number (158231409075).

Almost surely, 2^628706131909 is an apocalyptic number.

It is an amenable number.

628706131909 is a deficient number, since it is larger than the sum of its proper divisors (4219504391).

628706131909 is a wasteful number, since it uses less digits than its factorization.

628706131909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4219504390.

The product of its (nonzero) digits is 979776, while the sum is 52.

The spelling of 628706131909 in words is "six hundred twenty-eight billion, seven hundred six million, one hundred thirty-one thousand, nine hundred nine".