28005502505557 has 2 divisors, whose sum is σ = 28005502505558. Its totient is φ = 28005502505556.

The previous prime is 28005502505509. The next prime is 28005502505599. The reversal of 28005502505557 is 75550520550082.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21956431121361 + 6049071384196 = 4685769^2 + 2459486^2 .

It is a cyclic number.

It is not a de Polignac number, because 28005502505557 - 2¹⁵ = 28005502472789 is a prime.

It is a super-3 number, since 3×28005502505557³ (a number of 41 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 28005502505557.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28005502505657) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14002751252778 + 14002751252779.

It is an arithmetic number, because the mean of its divisors is an integer number (14002751252779).

Almost surely, 2^{28005502505557} is an apocalyptic number.

It is an amenable number.

28005502505557 is a deficient number, since it is larger than the sum of its proper divisors (1).

28005502505557 is an equidigital number, since it uses as much as digits as its factorization.

28005502505557 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3500000, while the sum is 49.

The spelling of 28005502505557 in words is "twenty-eight trillion, five billion, five hundred two million, five hundred five thousand, five hundred fifty-seven".