28381669 has 8 divisors (see below), whose sum is σ = 29008800. Its totient is φ = 27760656.

The previous prime is 28381667. The next prime is 28381673. The reversal of 28381669 is 96618382.

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 28381669 - 2¹ = 28381667 is a prime.

It is a super-2 number, since 2×28381669² = 1611038270451122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28381663) 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, 8562 + ... + 11404.

It is an arithmetic number, because the mean of its divisors is an integer number (3626100).

Almost surely, 2^28381669 is an apocalyptic number.

It is an amenable number.

28381669 is a deficient number, since it is larger than the sum of its proper divisors (627131).

28381669 is a wasteful number, since it uses less digits than its factorization.

28381669 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3059.

The product of its digits is 124416, while the sum is 43.

The square root of 28381669 is about 5327.4448847454. Note that the first 3 decimals coincide. The cubic root of 28381669 is about 305.0324036163.

The spelling of 28381669 in words is "twenty-eight million, three hundred eighty-one thousand, six hundred sixty-nine".