393844388 has 48 divisors (see below), whose sum is σ = 839731200. Its totient is φ = 157865760.

The previous prime is 393844343. The next prime is 393844393. The reversal of 393844388 is 883448393.

It is a super-2 number, since 2×393844388² = 310226803918189088, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 37343 + ... + 46713.

It is an arithmetic number, because the mean of its divisors is an integer number (17494400).

Almost surely, 2^393844388 is an apocalyptic number.

393844388 is a gapful number since it is divisible by the number (38) 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 393844388, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (419865600).

393844388 is an abundant number, since it is smaller than the sum of its proper divisors (445886812).

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

393844388 is a wasteful number, since it uses less digits than its factorization.

393844388 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9480 (or 9478 counting only the distinct ones).

The product of its digits is 1990656, while the sum is 50.

The square root of 393844388 is about 19845.5130445146. The cubic root of 393844388 is about 733.0071661540.

The spelling of 393844388 in words is "three hundred ninety-three million, eight hundred forty-four thousand, three hundred eighty-eight".