209794838378 has 16 divisors (see below), whose sum is σ = 314911086336. Its totient is φ = 104824507200.

The previous prime is 209794838377. The next prime is 209794838401. The reversal of 209794838378 is 873838497902.

It is a happy number.

It is a super-2 number, since 2×209794838378² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (209794838377) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26342225 + ... + 26350187.

It is an arithmetic number, because the mean of its divisors is an integer number (19681942896).

Almost surely, 2^209794838378 is an apocalyptic number.

209794838378 is a deficient number, since it is larger than the sum of its proper divisors (105116247958).

209794838378 is a wasteful number, since it uses less digits than its factorization.

209794838378 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15469.

The product of its (nonzero) digits is 146313216, while the sum is 68.

The spelling of 209794838378 in words is "two hundred nine billion, seven hundred ninety-four million, eight hundred thirty-eight thousand, three hundred seventy-eight".