28408697856 has 1056 divisors, whose sum is σ = 112404864000. Its totient is φ = 6827950080.

The previous prime is 28408697831. The next prime is 28408697857. The reversal of 28408697856 is 65879680482.

It is a tau number, because it is divible by the number of its divisors (1056).

It is a super-2 number, since 2×28408697856² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a junction number, because it is equal to n+sod(n) for n = 28408697793 and 28408697802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28408697857) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 660667371 + ... + 660667413.

It is an arithmetic number, because the mean of its divisors is an integer number (106444000).

Almost surely, 2^28408697856 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28408697856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (56202432000).

28408697856 is an abundant number, since it is smaller than the sum of its proper divisors (83996166144).

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

28408697856 is a wasteful number, since it uses less digits than its factorization.

28408697856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 120 (or 85 counting only the distinct ones).

The product of its (nonzero) digits is 46448640, while the sum is 63.

The spelling of 28408697856 in words is "twenty-eight billion, four hundred eight million, six hundred ninety-seven thousand, eight hundred fifty-six".