28161381100 has 18 divisors (see below), whose sum is σ = 61110197204. Its totient is φ = 11264552400.

The previous prime is 28161381047. The next prime is 28161381109. The reversal of 28161381100 is 118316182.

It is not an unprimeable number, because it can be changed into a prime (28161381109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 140806806 + ... + 140807005.

Almost surely, 2^28161381100 is an apocalyptic number.

28161381100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28161381100 is an abundant number, since it is smaller than the sum of its proper divisors (32948816104).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28161381100 is a wasteful number, since it uses less digits than its factorization.

28161381100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 281613825 (or 281613818 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 31.

Adding to 28161381100 its reverse (118316182), we get a palindrome (28279697282).

The spelling of 28161381100 in words is "twenty-eight billion, one hundred sixty-one million, three hundred eighty-one thousand, one hundred".