28919721600 has 2016 divisors, whose sum is σ = 141836948640. Its totient is φ = 5748019200.

The previous prime is 28919721569. The next prime is 28919721613. The reversal of 28919721600 is 612791982.

28919721600 is a `hidden beast` number, since 2 + 8 + 9 + 19 + 7 + 21 + 600 = 666.

It is a tau number, because it is divible by the number of its divisors (2016).

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 251 ways as a sum of consecutive naturals, for example, 1257379189 + ... + 1257379211.

Almost surely, 2^28919721600 is an apocalyptic number.

28919721600 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 28919721600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (70918474320).

28919721600 is an abundant number, since it is smaller than the sum of its proper divisors (112917227040).

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

28919721600 is a wasteful number, since it uses less digits than its factorization.

28919721600 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90 (or 51 counting only the distinct ones).

The product of its (nonzero) digits is 108864, while the sum is 45.

The spelling of 28919721600 in words is "twenty-eight billion, nine hundred nineteen million, seven hundred twenty-one thousand, six hundred".