209020900 has 144 divisors (see below), whose sum is σ = 531840960. Its totient is φ = 70502400.

The previous prime is 209020841. The next prime is 209020901. The reversal of 209020900 is 9020902.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is not an unprimeable number, because it can be changed into a prime (209020901) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1525632 + ... + 1525768.

It is an arithmetic number, because the mean of its divisors is an integer number (3693340).

Almost surely, 2^209020900 is an apocalyptic number.

209020900 is a gapful number since it is divisible by the number (20) 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 209020900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (265920480).

209020900 is an abundant number, since it is smaller than the sum of its proper divisors (322820060).

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

209020900 is a wasteful number, since it uses less digits than its factorization.

209020900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 254 (or 247 counting only the distinct ones).

The product of its (nonzero) digits is 324, while the sum is 22.

The square root of 209020900 is about 14457.5551183456. Note that the first 3 decimals coincide. The cubic root of 209020900 is about 593.4669949544.

The spelling of 209020900 in words is "two hundred nine million, twenty thousand, nine hundred".