28400047 has 16 divisors (see below), whose sum is σ = 32713632. Its totient is φ = 24422400.

The previous prime is 28400039. The next prime is 28400051. The reversal of 28400047 is 74000482.

It is a cyclic number.

It is not a de Polignac number, because 28400047 - 2³ = 28400039 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28399994 and 28400030.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28400017) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23047 + ... + 24247.

It is an arithmetic number, because the mean of its divisors is an integer number (2044602).

Almost surely, 2^28400047 is an apocalyptic number.

28400047 is a deficient number, since it is larger than the sum of its proper divisors (4313585).

28400047 is a wasteful number, since it uses less digits than its factorization.

28400047 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1338.

The product of its (nonzero) digits is 1792, while the sum is 25.

The square root of 28400047 is about 5329.1694474843. The cubic root of 28400047 is about 305.0982286852.

The spelling of 28400047 in words is "twenty-eight million, four hundred thousand, forty-seven".