209887240 has 32 divisors (see below), whose sum is σ = 472726080. Its totient is φ = 83869632.

The previous prime is 209887231. The next prime is 209887247. The reversal of 209887240 is 42788902.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 209887193 and 209887202.

It is not an unprimeable number, because it can be changed into a prime (209887247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 50107 + ... + 54133.

It is an arithmetic number, because the mean of its divisors is an integer number (14772690).

Almost surely, 2^209887240 is an apocalyptic number.

209887240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

209887240 is an abundant number, since it is smaller than the sum of its proper divisors (262838840).

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

209887240 is a wasteful number, since it uses less digits than its factorization.

209887240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5341 (or 5337 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 40.

The square root of 209887240 is about 14487.4856341603. The cubic root of 209887240 is about 594.2857894609.

The spelling of 209887240 in words is "two hundred nine million, eight hundred eighty-seven thousand, two hundred forty".