28888588721 has 2 divisors, whose sum is σ = 28888588722. Its totient is φ = 28888588720.

The previous prime is 28888588717. The next prime is 28888588739. The reversal of 28888588721 is 12788588882.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 26817337600 + 2071251121 = 163760^2 + 45511^2 .

It is a cyclic number.

It is not a de Polignac number, because 28888588721 - 2² = 28888588717 is a prime.

It is not a weakly prime, because it can be changed into another prime (28888288721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14444294360 + 14444294361.

It is an arithmetic number, because the mean of its divisors is an integer number (14444294361).

Almost surely, 2^28888588721 is an apocalyptic number.

It is an amenable number.

28888588721 is a deficient number, since it is larger than the sum of its proper divisors (1).

28888588721 is an equidigital number, since it uses as much as digits as its factorization.

28888588721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36700160, while the sum is 65.

The spelling of 28888588721 in words is "twenty-eight billion, eight hundred eighty-eight million, five hundred eighty-eight thousand, seven hundred twenty-one".