28777320 has 288 divisors, whose sum is σ = 113050080. Its totient is φ = 6289920.

The previous prime is 28777313. The next prime is 28777327. The reversal of 28777320 is 2377782.

It is an interprime number because it is at equal distance from previous prime (28777313) and next prime (28777327).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (28777327) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 669219 + ... + 669261.

It is an arithmetic number, because the mean of its divisors is an integer number (392535).

Almost surely, 2^28777320 is an apocalyptic number.

28777320 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 28777320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (56525040).

28777320 is an abundant number, since it is smaller than the sum of its proper divisors (84272760).

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

28777320 is a wasteful number, since it uses less digits than its factorization.

28777320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97 (or 77 counting only the distinct ones).

The product of its (nonzero) digits is 32928, while the sum is 36.

The square root of 28777320 is about 5364.4496455834. The cubic root of 28777320 is about 306.4432893364.

The spelling of 28777320 in words is "twenty-eight million, seven hundred seventy-seven thousand, three hundred twenty".