28299780 has 96 divisors (see below), whose sum is σ = 89268480. Its totient is φ = 7534944.

The previous prime is 28299769. The next prime is 28299793. The reversal of 28299780 is 8799282.

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

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 43417 + ... + 44063.

It is an arithmetic number, because the mean of its divisors is an integer number (929880).

Almost surely, 2^28299780 is an apocalyptic number.

28299780 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 28299780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44634240).

28299780 is an abundant number, since it is smaller than the sum of its proper divisors (60968700).

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

28299780 is an equidigital number, since it uses as much as digits as its factorization.

28299780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 677 (or 657 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 45.

The square root of 28299780 is about 5319.7537536995. The cubic root of 28299780 is about 304.7387532714.

The spelling of 28299780 in words is "twenty-eight million, two hundred ninety-nine thousand, seven hundred eighty".