209390641 has 4 divisors (see below), whose sum is σ = 209890800. Its totient is φ = 208890484.

The previous prime is 209390639. The next prime is 209390653. The reversal of 209390641 is 146093902.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 209390641 - 2¹ = 209390639 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 209390597 and 209390606.

It is not an unprimeable number, because it can be changed into a prime (209790641) 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 3 ways as a sum of consecutive naturals, for example, 249451 + ... + 250288.

It is an arithmetic number, because the mean of its divisors is an integer number (52472700).

Almost surely, 2^209390641 is an apocalyptic number.

It is an amenable number.

209390641 is a deficient number, since it is larger than the sum of its proper divisors (500159).

209390641 is an equidigital number, since it uses as much as digits as its factorization.

209390641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 500158.

The product of its (nonzero) digits is 11664, while the sum is 34.

The square root of 209390641 is about 14470.3365890362. The cubic root of 209390641 is about 593.8167204653.

The spelling of 209390641 in words is "two hundred nine million, three hundred ninety thousand, six hundred forty-one".