28973256857 has 2 divisors, whose sum is σ = 28973256858. Its totient is φ = 28973256856.

The previous prime is 28973256847. The next prime is 28973256863. The reversal of 28973256857 is 75865237982.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 25109888521 + 3863368336 = 158461^2 + 62156^2 .

It is a cyclic number.

It is not a de Polignac number, because 28973256857 - 2¹⁴ = 28973240473 is a prime.

It is a super-2 number, since 2×28973256857² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 28973256857.

It is not a weakly prime, because it can be changed into another prime (28973256847) 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, 14486628428 + 14486628429.

It is an arithmetic number, because the mean of its divisors is an integer number (14486628429).

Almost surely, 2^28973256857 is an apocalyptic number.

It is an amenable number.

28973256857 is a deficient number, since it is larger than the sum of its proper divisors (1).

28973256857 is an equidigital number, since it uses as much as digits as its factorization.

28973256857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 50803200, while the sum is 62.

The spelling of 28973256857 in words is "twenty-eight billion, nine hundred seventy-three million, two hundred fifty-six thousand, eight hundred fifty-seven".