28262689728 has 448 divisors, whose sum is σ = 95082774528. Its totient is φ = 7211151360.

The previous prime is 28262689699. The next prime is 28262689729. The reversal of 28262689728 is 82798626282.

It is a tau number, because it is divible by the number of its divisors (448).

It is a super-2 number, since 2×28262689728² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28262689729) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 104290233 + ... + 104290503.

It is an arithmetic number, because the mean of its divisors is an integer number (212238336).

Almost surely, 2^28262689728 is an apocalyptic number.

28262689728 is a gapful number since it is divisible by the number (28) 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 28262689728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47541387264).

28262689728 is an abundant number, since it is smaller than the sum of its proper divisors (66820084800).

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

28262689728 is a wasteful number, since it uses less digits than its factorization.

28262689728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 480 (or 470 counting only the distinct ones).

The product of its digits is 18579456, while the sum is 60.

The spelling of 28262689728 in words is "twenty-eight billion, two hundred sixty-two million, six hundred eighty-nine thousand, seven hundred twenty-eight".