28171740 has 24 divisors (see below), whose sum is σ = 78881040. Its totient is φ = 7512448.

The previous prime is 28171739. The next prime is 28171747. The reversal of 28171740 is 4717182.

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

It is a junction number, because it is equal to n+sod(n) for n = 28171698 and 28171707.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28171747) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 234705 + ... + 234824.

It is an arithmetic number, because the mean of its divisors is an integer number (3286710).

Almost surely, 2^28171740 is an apocalyptic number.

28171740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28171740 is an abundant number, since it is smaller than the sum of its proper divisors (50709300).

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

28171740 is a wasteful number, since it uses less digits than its factorization.

28171740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 469541 (or 469539 counting only the distinct ones).

The product of its (nonzero) digits is 3136, while the sum is 30.

The square root of 28171740 is about 5307.7057190466. The cubic root of 28171740 is about 304.2784700227.

The spelling of 28171740 in words is "twenty-eight million, one hundred seventy-one thousand, seven hundred forty".