28249643520 has 480 divisors, whose sum is σ = 112927022208. Its totient is φ = 6392807424.

The previous prime is 28249643519. The next prime is 28249643537. The reversal of 28249643520 is 2534694282.

28249643520 is a `hidden beast` number, since 2 + 82 + 4 + 9 + 6 + 43 + 520 = 666.

It is a tau number, because it is divible by the number of its divisors (480).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 17256142 + ... + 17257778.

Almost surely, 2^28249643520 is an apocalyptic number.

28249643520 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 28249643520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (56463511104).

28249643520 is an abundant number, since it is smaller than the sum of its proper divisors (84677378688).

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

28249643520 is a wasteful number, since it uses less digits than its factorization.

28249643520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1780 (or 1761 counting only the distinct ones).

The product of its (nonzero) digits is 829440, while the sum is 45.

The spelling of 28249643520 in words is "twenty-eight billion, two hundred forty-nine million, six hundred forty-three thousand, five hundred twenty".