28154484821 has 2 divisors, whose sum is σ = 28154484822. Its totient is φ = 28154484820.

The previous prime is 28154484793. The next prime is 28154484877. The reversal of 28154484821 is 12848445182.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14741602225 + 13412882596 = 121415^2 + 115814^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28154484821 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28154480821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14077242410 + 14077242411.

It is an arithmetic number, because the mean of its divisors is an integer number (14077242411).

Almost surely, 2^28154484821 is an apocalyptic number.

It is an amenable number.

28154484821 is a deficient number, since it is larger than the sum of its proper divisors (1).

28154484821 is an equidigital number, since it uses as much as digits as its factorization.

28154484821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 655360, while the sum is 47.

The spelling of 28154484821 in words is "twenty-eight billion, one hundred fifty-four million, four hundred eighty-four thousand, eight hundred twenty-one".