28288172640 has 384 divisors, whose sum is σ = 112229010432. Its totient is φ = 5829304320.

The previous prime is 28288172639. The next prime is 28288172651. The reversal of 28288172640 is 4627188282.

It is a super-2 number, since 2×28288172640² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 28288172640.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1870710 + ... + 1885770.

It is an arithmetic number, because the mean of its divisors is an integer number (292263048).

Almost surely, 2^28288172640 is an apocalyptic number.

28288172640 is a gapful number since it is divisible by the number (20) 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 28288172640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (56114505216).

28288172640 is an abundant number, since it is smaller than the sum of its proper divisors (83940837792).

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

28288172640 is a wasteful number, since it uses less digits than its factorization.

28288172640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15142 (or 15134 counting only the distinct ones).

The product of its (nonzero) digits is 688128, while the sum is 48.

The spelling of 28288172640 in words is "twenty-eight billion, two hundred eighty-eight million, one hundred seventy-two thousand, six hundred forty".