209197285440 has 896 divisors, whose sum is σ = 802260910080. Its totient is φ = 45790617600.

The previous prime is 209197285411. The next prime is 209197285499. The reversal of 209197285440 is 44582791902.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 1647222657 + ... + 1647222783.

It is an arithmetic number, because the mean of its divisors is an integer number (895380480).

Almost surely, 2^209197285440 is an apocalyptic number.

209197285440 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 209197285440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (401130455040).

209197285440 is an abundant number, since it is smaller than the sum of its proper divisors (593063624640).

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

209197285440 is a wasteful number, since it uses less digits than its factorization.

209197285440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 268 (or 232 counting only the distinct ones).

The product of its (nonzero) digits is 1451520, while the sum is 51.

The spelling of 209197285440 in words is "two hundred nine billion, one hundred ninety-seven million, two hundred eighty-five thousand, four hundred forty".