1628266628261 has 20 divisors (see below), whose sum is σ = 2045649209772. Its totient is φ = 1288298846016.

The previous prime is 1628266628251. The next prime is 1628266628273.

It is a happy number.

1628266628261 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in 2 ways, for example, as 73132925761 + 1555133702500 = 270431^2 + 1247050^2 .

It is not a de Polignac number, because 1628266628261 - 2¹⁰ = 1628266627237 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1628266628197 and 1628266628206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1628266628251) 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 19 ways as a sum of consecutive naturals, for example, 26051936 + ... + 26114361.

Almost surely, 2^{1628266628261} is an apocalyptic number.

It is an amenable number.

1628266628261 is a deficient number, since it is larger than the sum of its proper divisors (417382581511).

1628266628261 is an frugal number, since it uses more digits than its factorization.

1628266628261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52166338 (or 52166317 counting only the distinct ones).

The product of its digits is 7962624, while the sum is 56.

The spelling of 1628266628261 in words is "one trillion, six hundred twenty-eight billion, two hundred sixty-six million, six hundred twenty-eight thousand, two hundred sixty-one".