28990765440 has 1536 divisors, whose sum is σ = 134730086400. Its totient is φ = 5573836800.

The previous prime is 28990765423. The next prime is 28990765451. The reversal of 28990765440 is 4456709982.

28990765440 is a `hidden beast` number, since 2 + 8 + 9 + 90 + 7 + 6 + 544 + 0 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 408320605 + ... + 408320675.

It is an arithmetic number, because the mean of its divisors is an integer number (87714900).

Almost surely, 2^28990765440 is an apocalyptic number.

28990765440 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 28990765440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (67365043200).

28990765440 is an abundant number, since it is smaller than the sum of its proper divisors (105739320960).

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

28990765440 is a wasteful number, since it uses less digits than its factorization.

28990765440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 176 (or 161 counting only the distinct ones).

The product of its (nonzero) digits is 4354560, while the sum is 54.

It can be divided in two parts, 28990 and 765440, that added together give a triangular number (794430 = T₁₂₆₀).

The spelling of 28990765440 in words is "twenty-eight billion, nine hundred ninety million, seven hundred sixty-five thousand, four hundred forty".