28779520 has 176 divisors, whose sum is σ = 87251328. Its totient is φ = 8847360.

The previous prime is 28779473. The next prime is 28779529. The reversal of 28779520 is 2597782.

It is a tau number, because it is divible by the number of its divisors (176).

It is a Harshad number since it is a multiple of its sum of digits (40).

It is not an unprimeable number, because it can be changed into a prime (28779529) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 394204 + ... + 394276.

Almost surely, 2^28779520 is an apocalyptic number.

28779520 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 28779520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43625664).

28779520 is an abundant number, since it is smaller than the sum of its proper divisors (58471808).

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

28779520 is a wasteful number, since it uses less digits than its factorization.

28779520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116 (or 98 counting only the distinct ones).

The product of its (nonzero) digits is 70560, while the sum is 40.

The square root of 28779520 is about 5364.6546953182. The cubic root of 28779520 is about 306.4510982412.

The spelling of 28779520 in words is "twenty-eight million, seven hundred seventy-nine thousand, five hundred twenty".