623630828209 has 9 divisors (see below), whose sum is σ = 627239101419. Its totient is φ = 620043207480.

The previous prime is 623630828207. The next prime is 623630828257. The reversal of 623630828209 is 902828036326.

The square root of 623630828209 is 789703.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 6871912609 + 616758915600 = 82897^2 + 785340^2 .

It is not a de Polignac number, because 623630828209 - 2¹ = 623630828207 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (623630828207) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 142934062 + ... + 142938424.

It is an arithmetic number, because the mean of its divisors is an integer number (69693233491).

Almost surely, 2^623630828209 is an apocalyptic number.

623630828209 is the 789703-rd square number.

623630828209 is the 394852-nd centered octagonal number.

It is an amenable number.

623630828209 is a deficient number, since it is larger than the sum of its proper divisors (3608273210).

623630828209 is an frugal number, since it uses more digits than its factorization.

623630828209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9088 (or 4544 counting only the distinct ones).

The product of its (nonzero) digits is 1492992, while the sum is 49.

Multiplying 623630828209 by its sum of digits (49), we get a square (30557910582241 = 5527921²).

The spelling of 623630828209 in words is "six hundred twenty-three billion, six hundred thirty million, eight hundred twenty-eight thousand, two hundred nine".