28418707621 has 2 divisors, whose sum is σ = 28418707622. Its totient is φ = 28418707620.

The previous prime is 28418707589. The next prime is 28418707631. The reversal of 28418707621 is 12670781482.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27327726721 + 1090980900 = 165311^2 + 33030^2 .

It is a cyclic number.

It is not a de Polignac number, because 28418707621 - 2⁵ = 28418707589 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28418707631) 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 as a sum of consecutive naturals, namely, 14209353810 + 14209353811.

It is an arithmetic number, because the mean of its divisors is an integer number (14209353811).

Almost surely, 2^28418707621 is an apocalyptic number.

It is an amenable number.

28418707621 is a deficient number, since it is larger than the sum of its proper divisors (1).

28418707621 is an equidigital number, since it uses as much as digits as its factorization.

28418707621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 301056, while the sum is 46.

The spelling of 28418707621 in words is "twenty-eight billion, four hundred eighteen million, seven hundred seven thousand, six hundred twenty-one".