28911241780 has 48 divisors (see below), whose sum is σ = 62194144320. Its totient is φ = 11283084288.

The previous prime is 28911241721. The next prime is 28911241829. The reversal of 28911241780 is 8714211982.

It is a Harshad number since it is a multiple of its sum of digits (43).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 780847 + ... + 817033.

It is an arithmetic number, because the mean of its divisors is an integer number (1295711340).

Almost surely, 2^28911241780 is an apocalyptic number.

28911241780 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 28911241780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31097072160).

28911241780 is an abundant number, since it is smaller than the sum of its proper divisors (33282902540).

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

28911241780 is a wasteful number, since it uses less digits than its factorization.

28911241780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37168 (or 37166 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 43.

The spelling of 28911241780 in words is "twenty-eight billion, nine hundred eleven million, two hundred forty-one thousand, seven hundred eighty".