28636885581181 has 4 divisors (see below), whose sum is σ = 28636987275072. Its totient is φ = 28636783887292.

The previous prime is 28636885581173. The next prime is 28636885581191. The reversal of 28636885581181 is 18118558863682.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 28636885581181 - 2³ = 28636885581173 is a prime.

It is a super-2 number, since 2×28636885581181² (a number of 28 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28636885581181.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28636885581191) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 50423371 + ... + 50988136.

It is an arithmetic number, because the mean of its divisors is an integer number (7159246818768).

Almost surely, 2^{28636885581181} is an apocalyptic number.

It is an amenable number.

28636885581181 is a deficient number, since it is larger than the sum of its proper divisors (101693891).

28636885581181 is a wasteful number, since it uses less digits than its factorization.

28636885581181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101693890.

The product of its digits is 176947200, while the sum is 70.

The spelling of 28636885581181 in words is "twenty-eight trillion, six hundred thirty-six billion, eight hundred eighty-five million, five hundred eighty-one thousand, one hundred eighty-one".