28891228860 has 72 divisors (see below), whose sum is σ = 94378021920. Its totient is φ = 7111686528.

The previous prime is 28891228843. The next prime is 28891228921. The reversal of 28891228860 is 6882219882.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 28891228797 and 28891228806.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6171000 + ... + 6175679.

It is an arithmetic number, because the mean of its divisors is an integer number (1310805860).

Almost surely, 2^28891228860 is an apocalyptic number.

28891228860 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28891228860 is an abundant number, since it is smaller than the sum of its proper divisors (65486793060).

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

28891228860 is a wasteful number, since it uses less digits than its factorization.

28891228860 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12346707 (or 12346702 counting only the distinct ones).

The product of its (nonzero) digits is 1769472, while the sum is 54.

It can be divided in two parts, 2889122 and 8860, that added together give a palindrome (2897982).

The spelling of 28891228860 in words is "twenty-eight billion, eight hundred ninety-one million, two hundred twenty-eight thousand, eight hundred sixty".