28726686720 has 352 divisors, whose sum is σ = 107472412800. Its totient is φ = 7256604672.

The previous prime is 28726686679. The next prime is 28726686727. The reversal of 28726686720 is 2768662782.

28726686720 is a `hidden beast` number, since 287 + 266 + 86 + 7 + 20 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28726686727) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2621092 + ... + 2632028.

Almost surely, 2^28726686720 is an apocalyptic number.

28726686720 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 28726686720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (53736206400).

28726686720 is an abundant number, since it is smaller than the sum of its proper divisors (78745726080).

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

28726686720 is a wasteful number, since it uses less digits than its factorization.

28726686720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10990 (or 10966 counting only the distinct ones).

The product of its (nonzero) digits is 5419008, while the sum is 54.

The spelling of 28726686720 in words is "twenty-eight billion, seven hundred twenty-six million, six hundred eighty-six thousand, seven hundred twenty".