28268660621 has 2 divisors, whose sum is σ = 28268660622. Its totient is φ = 28268660620.

The previous prime is 28268660593. The next prime is 28268660683. The reversal of 28268660621 is 12606686282.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 25660515721 + 2608144900 = 160189^2 + 51070^2 .

It is a cyclic number.

It is not a de Polignac number, because 28268660621 - 2⁶ = 28268660557 is a prime.

It is a super-2 number, since 2×28268660621² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28268660521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14134330310 + 14134330311.

It is an arithmetic number, because the mean of its divisors is an integer number (14134330311).

Almost surely, 2^28268660621 is an apocalyptic number.

It is an amenable number.

28268660621 is a deficient number, since it is larger than the sum of its proper divisors (1).

28268660621 is an equidigital number, since it uses as much as digits as its factorization.

28268660621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 663552, while the sum is 47.

The spelling of 28268660621 in words is "twenty-eight billion, two hundred sixty-eight million, six hundred sixty thousand, six hundred twenty-one".