209621052 has 18 divisors (see below), whose sum is σ = 529875528. Its totient is φ = 69873672.

The previous prime is 209621051. The next prime is 209621059. The reversal of 209621052 is 250126902.

209621052 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209621051) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2911368 + ... + 2911439.

Almost surely, 2^209621052 is an apocalyptic number.

It is an amenable number.

209621052 is an abundant number, since it is smaller than the sum of its proper divisors (320254476).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

209621052 is a wasteful number, since it uses less digits than its factorization.

209621052 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5822817 (or 5822812 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 209621052 is about 14478.2958941997. The cubic root of 209621052 is about 594.0344502687.

Adding to 209621052 its reverse (250126902), we get a palindrome (459747954).

The spelling of 209621052 in words is "two hundred nine million, six hundred twenty-one thousand, fifty-two".