28381471 has 8 divisors (see below), whose sum is σ = 30338784. Its totient is φ = 26484480.

The previous prime is 28381453. The next prime is 28381511. The reversal of 28381471 is 17418382.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28381471 - 2⁵ = 28381439 is a prime.

It is a super-3 number, since 3×28381471³ (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28381411) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14106 + ... + 15991.

It is an arithmetic number, because the mean of its divisors is an integer number (3792348).

Almost surely, 2^28381471 is an apocalyptic number.

28381471 is a deficient number, since it is larger than the sum of its proper divisors (1957313).

28381471 is a wasteful number, since it uses less digits than its factorization.

28381471 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30161.

The product of its digits is 10752, while the sum is 34.

The square root of 28381471 is about 5327.4263016958. The cubic root of 28381471 is about 305.0316942787.

The spelling of 28381471 in words is "twenty-eight million, three hundred eighty-one thousand, four hundred seventy-one".