28538022521 has 2 divisors, whose sum is σ = 28538022522. Its totient is φ = 28538022520.

The previous prime is 28538022517. The next prime is 28538022529. The reversal of 28538022521 is 12522083582.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28271059600 + 266962921 = 168140^2 + 16339^2 .

It is a cyclic number.

It is not a de Polignac number, because 28538022521 - 2² = 28538022517 is a prime.

It is not a weakly prime, because it can be changed into another prime (28538022529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14269011260 + 14269011261.

It is an arithmetic number, because the mean of its divisors is an integer number (14269011261).

Almost surely, 2^28538022521 is an apocalyptic number.

It is an amenable number.

28538022521 is a deficient number, since it is larger than the sum of its proper divisors (1).

28538022521 is an equidigital number, since it uses as much as digits as its factorization.

28538022521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 76800, while the sum is 38.

The spelling of 28538022521 in words is "twenty-eight billion, five hundred thirty-eight million, twenty-two thousand, five hundred twenty-one".