628123709321 has 2 divisors, whose sum is σ = 628123709322. Its totient is φ = 628123709320.

The previous prime is 628123709261. The next prime is 628123709357. The reversal of 628123709321 is 123907321826.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 468074905600 + 160048803721 = 684160^2 + 400061^2 .

It is a cyclic number.

It is not a de Polignac number, because 628123709321 - 2¹⁰ = 628123708297 is a prime.

It is a super-2 number, since 2×628123709321² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (628123709621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 314061854660 + 314061854661.

It is an arithmetic number, because the mean of its divisors is an integer number (314061854661).

Almost surely, 2^628123709321 is an apocalyptic number.

It is an amenable number.

628123709321 is a deficient number, since it is larger than the sum of its proper divisors (1).

628123709321 is an equidigital number, since it uses as much as digits as its factorization.

628123709321 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 217728, while the sum is 44.

The spelling of 628123709321 in words is "six hundred twenty-eight billion, one hundred twenty-three million, seven hundred nine thousand, three hundred twenty-one".