1240104209 has 2 divisors, whose sum is σ = 1240104210. Its totient is φ = 1240104208.

The previous prime is 1240104193. The next prime is 1240104211. The reversal of 1240104209 is 9024010421.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 831053584 + 409050625 = 28828^2 + 20225^2 .

It is an emirp because it is prime and its reverse (9024010421) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1240104209 - 2⁴ = 1240104193 is a prime.

Together with 1240104211, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1240104289) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 620052104 + 620052105.

It is an arithmetic number, because the mean of its divisors is an integer number (620052105).

Almost surely, 2^1240104209 is an apocalyptic number.

It is an amenable number.

1240104209 is a deficient number, since it is larger than the sum of its proper divisors (1).

1240104209 is an equidigital number, since it uses as much as digits as its factorization.

1240104209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 1240104209 is about 35215.1133606013. The cubic root of 1240104209 is about 1074.3671657351.

The spelling of 1240104209 in words is "one billion, two hundred forty million, one hundred four thousand, two hundred nine".