28537709225281 has 2 divisors, whose sum is σ = 28537709225282. Its totient is φ = 28537709225280.

The previous prime is 28537709225239. The next prime is 28537709225317. The reversal of 28537709225281 is 18252290773582.

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., 21956637295681 + 6581071929600 = 4685791^2 + 2565360^2 .

It is a cyclic number.

It is not a de Polignac number, because 28537709225281 - 2²⁷ = 28537575007553 is a prime.

It is a super-2 number, since 2×28537709225281² (a number of 28 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (28537709225381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14268854612640 + 14268854612641.

It is an arithmetic number, because the mean of its divisors is an integer number (14268854612641).

Almost surely, 2^{28537709225281} is an apocalyptic number.

It is an amenable number.

28537709225281 is a deficient number, since it is larger than the sum of its proper divisors (1).

28537709225281 is an equidigital number, since it uses as much as digits as its factorization.

28537709225281 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 33868800, while the sum is 61.

The spelling of 28537709225281 in words is "twenty-eight trillion, five hundred thirty-seven billion, seven hundred nine million, two hundred twenty-five thousand, two hundred eighty-one".