28663821648 has 1080 divisors, whose sum is σ = 114610164480. Its totient is φ = 6825772800.

The previous prime is 28663821577. The next prime is 28663821649. The reversal of 28663821648 is 84612836682.

It is a super-2 number, since 2×28663821648² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 28663821594 and 28663821603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28663821649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 215 ways as a sum of consecutive naturals, for example, 924639393 + ... + 924639423.

Almost surely, 2^28663821648 is an apocalyptic number.

28663821648 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 28663821648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (57305082240).

28663821648 is an abundant number, since it is smaller than the sum of its proper divisors (85946342832).

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

28663821648 is a wasteful number, since it uses less digits than its factorization.

28663821648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122 (or 73 counting only the distinct ones).

The product of its digits is 5308416, while the sum is 54.

The spelling of 28663821648 in words is "twenty-eight billion, six hundred sixty-three million, eight hundred twenty-one thousand, six hundred forty-eight".