1228405 has 4 divisors (see below), whose sum is σ = 1474092. Its totient is φ = 982720.

The previous prime is 1228399. The next prime is 1228429. The reversal of 1228405 is 5048221.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 289444 + 938961 = 538^2 + 969^2 .

It is not a de Polignac number, because 1228405 - 2³ = 1228397 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 122836 + ... + 122845.

It is an arithmetic number, because the mean of its divisors is an integer number (368523).

2^1228405 is an apocalyptic number.

It is an amenable number.

1228405 is a deficient number, since it is larger than the sum of its proper divisors (245687).

1228405 is an equidigital number, since it uses as much as digits as its factorization.

1228405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 245686.

The product of its (nonzero) digits is 640, while the sum is 22.

The square root of 1228405 is about 1108.3343358391. The cubic root of 1228405 is about 107.0977939596.

The spelling of 1228405 in words is "one million, two hundred twenty-eight thousand, four hundred five".