28686435637 has 2 divisors, whose sum is σ = 28686435638. Its totient is φ = 28686435636.

The previous prime is 28686435593. The next prime is 28686435641. The reversal of 28686435637 is 73653468682.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27146187121 + 1540248516 = 164761^2 + 39246^2 .

It is a cyclic number.

It is not a de Polignac number, because 28686435637 - 2⁷ = 28686435509 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28686435677) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14343217818 + 14343217819.

It is an arithmetic number, because the mean of its divisors is an integer number (14343217819).

Almost surely, 2^28686435637 is an apocalyptic number.

It is an amenable number.

28686435637 is a deficient number, since it is larger than the sum of its proper divisors (1).

28686435637 is an equidigital number, since it uses as much as digits as its factorization.

28686435637 is an evil number, because the sum of its binary digits is even.

The product of its digits is 34836480, while the sum is 58.

The spelling of 28686435637 in words is "twenty-eight billion, six hundred eighty-six million, four hundred thirty-five thousand, six hundred thirty-seven".