1228905 has 16 divisors (see below), whose sum is σ = 2184960. Its totient is φ = 655344.

The previous prime is 1228891. The next prime is 1228907. The reversal of 1228905 is 5098221.

1228905 is nontrivially palindromic in base 2.

It is not a de Polignac number, because 1228905 - 2⁴ = 1228889 is a prime.

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (1228907) 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, 4417 + ... + 4686.

It is an arithmetic number, because the mean of its divisors is an integer number (136560).

2^1228905 is an apocalyptic number.

1228905 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1228905 is a deficient number, since it is larger than the sum of its proper divisors (956055).

1228905 is an equidigital number, since it uses as much as digits as its factorization.

1228905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9117 (or 9111 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The square root of 1228905 is about 1108.5598765967. The cubic root of 1228905 is about 107.1123227275.

The spelling of 1228905 in words is "one million, two hundred twenty-eight thousand, nine hundred five".