28165391380 has 96 divisors (see below), whose sum is σ = 71255439360. Its totient is φ = 9135504000.

The previous prime is 28165391377. The next prime is 28165391383. The reversal of 28165391380 is 8319356182.

It is an interprime number because it is at equal distance from previous prime (28165391377) and next prime (28165391383).

It is a self number, because there is not a number n which added to its sum of digits gives 28165391380.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28165391383) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1969255 + ... + 1983505.

It is an arithmetic number, because the mean of its divisors is an integer number (742244160).

Almost surely, 2^28165391380 is an apocalyptic number.

28165391380 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 28165391380, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35627719680).

28165391380 is an abundant number, since it is smaller than the sum of its proper divisors (43090047980).

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

28165391380 is a wasteful number, since it uses less digits than its factorization.

28165391380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15029 (or 15027 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 46.

The spelling of 28165391380 in words is "twenty-eight billion, one hundred sixty-five million, three hundred ninety-one thousand, three hundred eighty".