28091018664 has 96 divisors (see below), whose sum is σ = 79652008800. Its totient is φ = 8931807360.

The previous prime is 28091018663. The next prime is 28091018689. The reversal of 28091018664 is 46681019082.

It is not an unprimeable number, because it can be changed into a prime (28091018663) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 92259 + ... + 254349.

It is an arithmetic number, because the mean of its divisors is an integer number (829708425).

Almost surely, 2^28091018664 is an apocalyptic number.

28091018664 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28091018664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39826004400).

28091018664 is an abundant number, since it is smaller than the sum of its proper divisors (51560990136).

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

28091018664 is a wasteful number, since it uses less digits than its factorization.

28091018664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162215 (or 162208 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 45.

The spelling of 28091018664 in words is "twenty-eight billion, ninety-one million, eighteen thousand, six hundred sixty-four".