28749647556 has 144 divisors (see below), whose sum is σ = 85185959040. Its totient is φ = 8003888640.

The previous prime is 28749647527. The next prime is 28749647557. The reversal of 28749647556 is 65574694782.

28749647556 is a `hidden beast` number, since 2 + 8 + 74 + 9 + 6 + 4 + 7 + 556 = 666.

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 = 28749647493 and 28749647502.

It is not an unprimeable number, because it can be changed into a prime (28749647557) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 13192875 + ... + 13195053.

It is an arithmetic number, because the mean of its divisors is an integer number (591569160).

Almost surely, 2^28749647556 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 28749647556, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42592979520).

28749647556 is an abundant number, since it is smaller than the sum of its proper divisors (56436311484).

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

28749647556 is a wasteful number, since it uses less digits than its factorization.

28749647556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3514 (or 3509 counting only the distinct ones).

The product of its digits is 101606400, while the sum is 63.

The spelling of 28749647556 in words is "twenty-eight billion, seven hundred forty-nine million, six hundred forty-seven thousand, five hundred fifty-six".