1229905 has 4 divisors (see below), whose sum is σ = 1475892. Its totient is φ = 983920.

The previous prime is 1229903. The next prime is 1229911. The reversal of 1229905 is 5099221.

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 831744 + 398161 = 912^2 + 631^2 .

It is not a de Polignac number, because 1229905 - 2¹ = 1229903 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1229903) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 122986 + ... + 122995.

It is an arithmetic number, because the mean of its divisors is an integer number (368973).

2^1229905 is an apocalyptic number.

It is an amenable number.

1229905 is a deficient number, since it is larger than the sum of its proper divisors (245987).

1229905 is an equidigital number, since it uses as much as digits as its factorization.

1229905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 245986.

The product of its (nonzero) digits is 1620, while the sum is 28.

The square root of 1229905 is about 1109.0108205063. The cubic root of 1229905 is about 107.1413684449.

The spelling of 1229905 in words is "one million, two hundred twenty-nine thousand, nine hundred five".