209005056 has 160 divisors (see below), whose sum is σ = 666832320. Its totient is φ = 64253952.

The previous prime is 209005037. The next prime is 209005061. The reversal of 209005056 is 650500902.

It is a super-2 number, since 2×209005056² = 87366226867126272, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 179131 + ... + 180293.

It is an arithmetic number, because the mean of its divisors is an integer number (4167702).

Almost surely, 2^209005056 is an apocalyptic number.

209005056 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 209005056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (333416160).

209005056 is an abundant number, since it is smaller than the sum of its proper divisors (457827264).

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

209005056 is a wasteful number, since it uses less digits than its factorization.

209005056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1203 (or 1181 counting only the distinct ones).

The product of its (nonzero) digits is 2700, while the sum is 27.

The square root of 209005056 is about 14457.0071591599. The cubic root of 209005056 is about 593.4519994386.

Adding to 209005056 its reverse (650500902), we get a palindrome (859505958).

The spelling of 209005056 in words is "two hundred nine million, five thousand, fifty-six".