28187173687 has 2 divisors, whose sum is σ = 28187173688. Its totient is φ = 28187173686.

The previous prime is 28187173673. The next prime is 28187173717. The reversal of 28187173687 is 78637178182.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28187173687 - 2¹⁹ = 28186649399 is a prime.

It is a super-2 number, since 2×28187173687² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28187173667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14093586843 + 14093586844.

It is an arithmetic number, because the mean of its divisors is an integer number (14093586844).

Almost surely, 2^28187173687 is an apocalyptic number.

28187173687 is a deficient number, since it is larger than the sum of its proper divisors (1).

28187173687 is an equidigital number, since it uses as much as digits as its factorization.

28187173687 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6322176, while the sum is 58.

The spelling of 28187173687 in words is "twenty-eight billion, one hundred eighty-seven million, one hundred seventy-three thousand, six hundred eighty-seven".