28705080 has 64 divisors (see below), whose sum is σ = 88133760. Its totient is φ = 7475328.

The previous prime is 28705069. The next prime is 28705091. The reversal of 28705080 is 8050782.

It is an interprime number because it is at equal distance from previous prime (28705069) and next prime (28705091).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2379 + ... + 7941.

It is an arithmetic number, because the mean of its divisors is an integer number (1377090).

Almost surely, 2^28705080 is an apocalyptic number.

28705080 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 28705080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44066880).

28705080 is an abundant number, since it is smaller than the sum of its proper divisors (59428680).

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

28705080 is a wasteful number, since it uses less digits than its factorization.

28705080 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5620 (or 5616 counting only the distinct ones).

The product of its (nonzero) digits is 4480, while the sum is 30.

The square root of 28705080 is about 5357.7121983175. The cubic root of 28705080 is about 306.1866518980.

The spelling of 28705080 in words is "twenty-eight million, seven hundred five thousand, eighty".