209049421 has 4 divisors (see below), whose sum is σ = 238913632. Its totient is φ = 179185212.

The previous prime is 209049413. The next prime is 209049427. The reversal of 209049421 is 124940902.

It is a happy number.

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 209049421 - 2³ = 209049413 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209049427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14932095 + ... + 14932108.

It is an arithmetic number, because the mean of its divisors is an integer number (59728408).

Almost surely, 2^209049421 is an apocalyptic number.

It is an amenable number.

209049421 is a deficient number, since it is larger than the sum of its proper divisors (29864211).

209049421 is an equidigital number, since it uses as much as digits as its factorization.

209049421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29864210.

The product of its (nonzero) digits is 5184, while the sum is 31.

The square root of 209049421 is about 14458.5414547941. The cubic root of 209049421 is about 593.4939866769.

The spelling of 209049421 in words is "two hundred nine million, forty-nine thousand, four hundred twenty-one".