28281400692821 has 2 divisors, whose sum is σ = 28281400692822. Its totient is φ = 28281400692820.

The previous prime is 28281400692791. The next prime is 28281400692889. The reversal of 28281400692821 is 12829600418282.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24194691816100 + 4086708876721 = 4918810^2 + 2021561^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28281400692821 is a prime.

It is a super-2 number, since 2×28281400692821² (a number of 28 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28281400697821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14140700346410 + 14140700346411.

It is an arithmetic number, because the mean of its divisors is an integer number (14140700346411).

Almost surely, 2^{28281400692821} is an apocalyptic number.

It is an amenable number.

28281400692821 is a deficient number, since it is larger than the sum of its proper divisors (1).

28281400692821 is an equidigital number, since it uses as much as digits as its factorization.

28281400692821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1769472, while the sum is 53.

The spelling of 28281400692821 in words is "twenty-eight trillion, two hundred eighty-one billion, four hundred million, six hundred ninety-two thousand, eight hundred twenty-one".