209640364 has 12 divisors (see below), whose sum is σ = 367181584. Its totient is φ = 104731344.

The previous prime is 209640349. The next prime is 209640367. The reversal of 209640364 is 463046902.

It is not an unprimeable number, because it can be changed into a prime (209640367) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16752 + ... + 26455.

Almost surely, 2^209640364 is an apocalyptic number.

It is an amenable number.

209640364 is a deficient number, since it is larger than the sum of its proper divisors (157541220).

209640364 is a wasteful number, since it uses less digits than its factorization.

209640364 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44424 (or 44422 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 34.

The square root of 209640364 is about 14478.9628081572. The cubic root of 209640364 is about 594.0526921404.

The spelling of 209640364 in words is "two hundred nine million, six hundred forty thousand, three hundred sixty-four".