28277255821 has 2 divisors, whose sum is σ = 28277255822. Its totient is φ = 28277255820.

The previous prime is 28277255791. The next prime is 28277255849. The reversal of 28277255821 is 12855277282.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25845385225 + 2431870596 = 160765^2 + 49314^2 .

It is a cyclic number.

It is not a de Polignac number, because 28277255821 - 2⁵ = 28277255789 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28277253821) 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, 14138627910 + 14138627911.

It is an arithmetic number, because the mean of its divisors is an integer number (14138627911).

Almost surely, 2^28277255821 is an apocalyptic number.

It is an amenable number.

28277255821 is a deficient number, since it is larger than the sum of its proper divisors (1).

28277255821 is an equidigital number, since it uses as much as digits as its factorization.

28277255821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1254400, while the sum is 49.

The spelling of 28277255821 in words is "twenty-eight billion, two hundred seventy-seven million, two hundred fifty-five thousand, eight hundred twenty-one".