28479780 has 108 divisors (see below), whose sum is σ = 100524060. Its totient is φ = 6507648.

The previous prime is 28479761. The next prime is 28479797. The reversal of 28479780 is 8797482.

It can be written as a sum of positive squares in 2 ways, for example, as 9400356 + 19079424 = 3066^2 + 4368^2 .

It is a super-2 number, since 2×28479780² = 1622195737696800, which contains 22 as substring.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a nialpdrome in base 12.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 7206 + ... + 10434.

Almost surely, 2^28479780 is an apocalyptic number.

28479780 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 28479780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (50262030).

28479780 is an abundant number, since it is smaller than the sum of its proper divisors (72044280).

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

28479780 is a wasteful number, since it uses less digits than its factorization.

28479780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3258 (or 3246 counting only the distinct ones).

The product of its (nonzero) digits is 225792, while the sum is 45.

The square root of 28479780 is about 5336.6450134893. The cubic root of 28479780 is about 305.3834825218.

The spelling of 28479780 in words is "twenty-eight million, four hundred seventy-nine thousand, seven hundred eighty".