1242240209 has 12 divisors (see below), whose sum is σ = 1447447284. Its totient is φ = 1063014624.

The previous prime is 1242240179. The next prime is 1242240217. The reversal of 1242240209 is 9020422421.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 295324225 + 946915984 = 17185^2 + 30772^2 .

It is not a de Polignac number, because 1242240209 - 2⁸ = 1242239953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1242240229) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9359 + ... + 50715.

It is an arithmetic number, because the mean of its divisors is an integer number (120620607).

Almost surely, 2^1242240209 is an apocalyptic number.

It is an amenable number.

1242240209 is a deficient number, since it is larger than the sum of its proper divisors (205207075).

1242240209 is an equidigital number, since it uses as much as digits as its factorization.

1242240209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41984 (or 41977 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 26.

The square root of 1242240209 is about 35245.4281999808. The cubic root of 1242240209 is about 1074.9836547722.

The spelling of 1242240209 in words is "one billion, two hundred forty-two million, two hundred forty thousand, two hundred nine".