207242809 has 8 divisors (see below), whose sum is σ = 214955208. Its totient is φ = 199641600.

The previous prime is 207242807. The next prime is 207242837. The reversal of 207242809 is 908242702.

It can be written as a sum of positive squares in 4 ways, for example, as 53978409 + 153264400 = 7347^2 + 12380^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 207242809 - 2¹ = 207242807 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (207242807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23992 + ... + 31465.

It is an arithmetic number, because the mean of its divisors is an integer number (26869401).

Almost surely, 2^207242809 is an apocalyptic number.

It is an amenable number.

207242809 is a deficient number, since it is larger than the sum of its proper divisors (7712399).

207242809 is a wasteful number, since it uses less digits than its factorization.

207242809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55595.

The product of its (nonzero) digits is 16128, while the sum is 34.

The square root of 207242809 is about 14395.9302929682. The cubic root of 207242809 is about 591.7793730233.

The spelling of 207242809 in words is "two hundred seven million, two hundred forty-two thousand, eight hundred nine".