28404407 has 2 divisors, whose sum is σ = 28404408. Its totient is φ = 28404406.

The previous prime is 28404377. The next prime is 28404451. The reversal of 28404407 is 70440482.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28404407 - 2¹² = 28400311 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28404407.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28404457) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14202203 + 14202204.

It is an arithmetic number, because the mean of its divisors is an integer number (14202204).

Almost surely, 2^28404407 is an apocalyptic number.

28404407 is a deficient number, since it is larger than the sum of its proper divisors (1).

28404407 is an equidigital number, since it uses as much as digits as its factorization.

28404407 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7168, while the sum is 29.

The square root of 28404407 is about 5329.5785011575. The cubic root of 28404407 is about 305.1138408684.

Adding to 28404407 its reverse (70440482), we get a palindrome (98844889).

The spelling of 28404407 in words is "twenty-eight million, four hundred four thousand, four hundred seven".