28229637281 has 2 divisors, whose sum is σ = 28229637282. Its totient is φ = 28229637280.

The previous prime is 28229637269. The next prime is 28229637323. The reversal of 28229637281 is 18273692282.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24907152400 + 3322484881 = 157820^2 + 57641^2 .

It is a cyclic number.

It is not a de Polignac number, because 28229637281 - 2²² = 28225442977 is a prime.

It is a super-2 number, since 2×28229637281² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (28229837281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14114818640 + 14114818641.

It is an arithmetic number, because the mean of its divisors is an integer number (14114818641).

Almost surely, 2^28229637281 is an apocalyptic number.

It is an amenable number.

28229637281 is a deficient number, since it is larger than the sum of its proper divisors (1).

28229637281 is an equidigital number, since it uses as much as digits as its factorization.

28229637281 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1161216, while the sum is 50.

The spelling of 28229637281 in words is "twenty-eight billion, two hundred twenty-nine million, six hundred thirty-seven thousand, two hundred eighty-one".