209091128 has 8 divisors (see below), whose sum is σ = 392045880. Its totient is φ = 104545560.

The previous prime is 209091119. The next prime is 209091139. The reversal of 209091128 is 821190902.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (8).

It is a junction number, because it is equal to n+sod(n) for n = 209091094 and 209091103.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13068188 + ... + 13068203.

It is an arithmetic number, because the mean of its divisors is an integer number (49005735).

Almost surely, 2^209091128 is an apocalyptic number.

It is an amenable number.

209091128 is a deficient number, since it is larger than the sum of its proper divisors (182954752).

209091128 is a wasteful number, since it uses less digits than its factorization.

209091128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26136397 (or 26136393 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 32.

The square root of 209091128 is about 14459.9836791056. The cubic root of 209091128 is about 593.5334529550.

The spelling of 209091128 in words is "two hundred nine million, ninety-one thousand, one hundred twenty-eight".