1125684209 has 4 divisors (see below), whose sum is σ = 1212275316. Its totient is φ = 1039093104.

The previous prime is 1125684199. The next prime is 1125684211. The reversal of 1125684209 is 9024865211.

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 202435984 + 923248225 = 14228^2 + 30385^2 .

It is a cyclic number.

It is not a de Polignac number, because 1125684209 - 2⁸ = 1125683953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1125684269) 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, 43295534 + ... + 43295559.

It is an arithmetic number, because the mean of its divisors is an integer number (303068829).

Almost surely, 2^1125684209 is an apocalyptic number.

It is an amenable number.

1125684209 is a deficient number, since it is larger than the sum of its proper divisors (86591107).

1125684209 is an equidigital number, since it uses as much as digits as its factorization.

1125684209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86591106.

The product of its (nonzero) digits is 34560, while the sum is 38.

The square root of 1125684209 is about 33551.2176977230. The cubic root of 1125684209 is about 1040.2527150288.

The spelling of 1125684209 in words is "one billion, one hundred twenty-five million, six hundred eighty-four thousand, two hundred nine".