28911480 has 128 divisors (see below), whose sum is σ = 95800320. Its totient is φ = 6935040.

The previous prime is 28911469. The next prime is 28911481. The reversal of 28911480 is 8411982.

28911480 = T₁₂₉ + T₁₃₀ + ... + T₅₅₉.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28911481) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 66865 + ... + 67295.

It is an arithmetic number, because the mean of its divisors is an integer number (748440).

Almost surely, 2^28911480 is an apocalyptic number.

28911480 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 28911480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47900160).

28911480 is an abundant number, since it is smaller than the sum of its proper divisors (66888840).

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

28911480 is a wasteful number, since it uses less digits than its factorization.

28911480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 501 (or 497 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 33.

The square root of 28911480 is about 5376.9396500240. The cubic root of 28911480 is about 306.9187645587.

It can be divided in two parts, 2891 and 1480, that added together give a triangular number (4371 = T₉₃).

The spelling of 28911480 in words is "twenty-eight million, nine hundred eleven thousand, four hundred eighty".