28781444037887 has 2 divisors, whose sum is σ = 28781444037888. Its totient is φ = 28781444037886.

The previous prime is 28781444037869. The next prime is 28781444037889. The reversal of 28781444037887 is 78873044418782.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28781444037887 - 2⁶ = 28781444037823 is a prime.

It is a super-2 number, since 2×28781444037887² (a number of 28 digits) contains 22 as substring.

Together with 28781444037889, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28781444037887.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28781444037889) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14390722018943 + 14390722018944.

It is an arithmetic number, because the mean of its divisors is an integer number (14390722018944).

Almost surely, 2^{28781444037887} is an apocalyptic number.

28781444037887 is a deficient number, since it is larger than the sum of its proper divisors (1).

28781444037887 is an equidigital number, since it uses as much as digits as its factorization.

28781444037887 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 539492352, while the sum is 71.

The spelling of 28781444037887 in words is "twenty-eight trillion, seven hundred eighty-one billion, four hundred forty-four million, thirty-seven thousand, eight hundred eighty-seven".