209197945 has 8 divisors (see below), whose sum is σ = 273859200. Its totient is φ = 152143920.

The previous prime is 209197939. The next prime is 209197957. The reversal of 209197945 is 549791902.

It is a happy number.

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

It is not a de Polignac number, because 209197945 - 2⁵ = 209197913 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 209197895 and 209197904.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1901745 + ... + 1901854.

It is an arithmetic number, because the mean of its divisors is an integer number (34232400).

Almost surely, 2^209197945 is an apocalyptic number.

It is an amenable number.

209197945 is a deficient number, since it is larger than the sum of its proper divisors (64661255).

209197945 is a wasteful number, since it uses less digits than its factorization.

209197945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3803615.

The product of its (nonzero) digits is 204120, while the sum is 46.

The square root of 209197945 is about 14463.6767455582. The cubic root of 209197945 is about 593.6345072502.

The spelling of 209197945 in words is "two hundred nine million, one hundred ninety-seven thousand, nine hundred forty-five".