28763178217 has 2 divisors, whose sum is σ = 28763178218. Its totient is φ = 28763178216.

The previous prime is 28763178211. The next prime is 28763178239. The reversal of 28763178217 is 71287136782.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21580785216 + 7182393001 = 146904^2 + 84749^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28763178217 is a prime.

It is a super-2 number, since 2×28763178217² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (28763178211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14381589108 + 14381589109.

It is an arithmetic number, because the mean of its divisors is an integer number (14381589109).

Almost surely, 2^28763178217 is an apocalyptic number.

It is an amenable number.

28763178217 is a deficient number, since it is larger than the sum of its proper divisors (1).

28763178217 is an equidigital number, since it uses as much as digits as its factorization.

28763178217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1580544, while the sum is 52.

The spelling of 28763178217 in words is "twenty-eight billion, seven hundred sixty-three million, one hundred seventy-eight thousand, two hundred seventeen".