70209 has 12 divisors (see below), whose sum is σ = 105300. Its totient is φ = 45024.

The previous prime is 70207. The next prime is 70223. The reversal of 70209 is 90207.

70209 = 2² + 3² + ... + 59².

It can be written as a sum of positive squares in 2 ways, for example, as 18225 + 51984 = 135^2 + 228^2 .

It is not a de Polignac number, because 70209 - 2¹ = 70207 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 70191 and 70200.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 70209.

It is not an unprimeable number, because it can be changed into a prime (70201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 127 + ... + 395.

It is an arithmetic number, because the mean of its divisors is an integer number (8775).

2⁷⁰²⁰⁹ is an apocalyptic number.

It is an amenable number.

70209 is a deficient number, since it is larger than the sum of its proper divisors (35091).

70209 is a wasteful number, since it uses less digits than its factorization.

70209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 304 (or 301 counting only the distinct ones).

The product of its (nonzero) digits is 126, while the sum is 18.

The square root of 70209 is about 264.9698096010. The cubic root of 70209 is about 41.2538288457.

The spelling of 70209 in words is "seventy thousand, two hundred nine".