11428209 has 20 divisors (see below), whose sum is σ = 18386676. Its totient is φ = 7032096.

The previous prime is 11428201. The next prime is 11428237. The reversal of 11428209 is 90282411.

11428209 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 3744225 + 7683984 = 1935^2 + 2772^2 .

It is not a de Polignac number, because 11428209 - 2³ = 11428201 is a prime.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11428201) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 4374 + ... + 6479.

Almost surely, 2^11428209 is an apocalyptic number.

It is an amenable number.

11428209 is a deficient number, since it is larger than the sum of its proper divisors (6958467).

11428209 is a wasteful number, since it uses less digits than its factorization.

11428209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10878 (or 10869 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 11428209 is about 3380.5634145805. The cubic root of 11428209 is about 225.2471949878.

It can be divided in two parts, 1142820 and 9, that multiplied together give a triangular number (10285380 = T₄₅₃₅).

The spelling of 11428209 in words is "eleven million, four hundred twenty-eight thousand, two hundred nine".