209493040 has 80 divisors (see below), whose sum is σ = 532465920. Its totient is φ = 76308480.

The previous prime is 209493019. The next prime is 209493041. The reversal of 209493040 is 40394902.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a junction number, because it is equal to n+sod(n) for n = 209492993 and 209493011.

It is not an unprimeable number, because it can be changed into a prime (209493041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 39676 + ... + 44644.

It is an arithmetic number, because the mean of its divisors is an integer number (6655824).

Almost surely, 2^209493040 is an apocalyptic number.

209493040 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 209493040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (266232960).

209493040 is an abundant number, since it is smaller than the sum of its proper divisors (322972880).

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

209493040 is a wasteful number, since it uses less digits than its factorization.

209493040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5030 (or 5024 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 31.

The square root of 209493040 is about 14473.8743949227. The cubic root of 209493040 is about 593.9135034108.

The spelling of 209493040 in words is "two hundred nine million, four hundred ninety-three thousand, forty".