209742035 has 4 divisors (see below), whose sum is σ = 251690448. Its totient is φ = 167793624.

The previous prime is 209742031. The next prime is 209742061. The reversal of 209742035 is 530247902.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 530247902 = 2 ⋅265123951.

It is a cyclic number.

It is not a de Polignac number, because 209742035 - 2² = 209742031 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 209741992 and 209742010.

It is not an unprimeable number, because it can be changed into a prime (209742031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20974199 + ... + 20974208.

It is an arithmetic number, because the mean of its divisors is an integer number (62922612).

Almost surely, 2^209742035 is an apocalyptic number.

209742035 is a deficient number, since it is larger than the sum of its proper divisors (41948413).

209742035 is an equidigital number, since it uses as much as digits as its factorization.

209742035 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41948412.

The product of its (nonzero) digits is 15120, while the sum is 32.

The square root of 209742035 is about 14482.4733730119. The cubic root of 209742035 is about 594.1487108156.

Adding to 209742035 its reverse (530247902), we get a palindrome (739989937).

The spelling of 209742035 in words is "two hundred nine million, seven hundred forty-two thousand, thirty-five".