28321525780 has 144 divisors (see below), whose sum is σ = 64348010496. Its totient is φ = 10466184960.

The previous prime is 28321525777. The next prime is 28321525781. The reversal of 28321525780 is 8752512382.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28321525781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 61434750 + ... + 61435210.

It is an arithmetic number, because the mean of its divisors is an integer number (446861184).

Almost surely, 2^28321525780 is an apocalyptic number.

28321525780 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 28321525780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32174005248).

28321525780 is an abundant number, since it is smaller than the sum of its proper divisors (36026484716).

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

28321525780 is a wasteful number, since it uses less digits than its factorization.

28321525780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 702 (or 681 counting only the distinct ones).

The product of its (nonzero) digits is 268800, while the sum is 43.

The spelling of 28321525780 in words is "twenty-eight billion, three hundred twenty-one million, five hundred twenty-five thousand, seven hundred eighty".