391921344 has 168 divisors, whose sum is σ = 1186818048. Its totient is φ = 123471360.

The previous prime is 391921339. The next prime is 391921351. The reversal of 391921344 is 443129193.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 391921299 and 391921308.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 838999 + ... + 839465.

Almost surely, 2^391921344 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 391921344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (593409024).

391921344 is an abundant number, since it is smaller than the sum of its proper divisors (794896704).

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

391921344 is a wasteful number, since it uses less digits than its factorization.

391921344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 563 (or 550 counting only the distinct ones).

The product of its digits is 23328, while the sum is 36.

The square root of 391921344 is about 19797.0034096072. The cubic root of 391921344 is about 731.8121886707.

The spelling of 391921344 in words is "three hundred ninety-one million, nine hundred twenty-one thousand, three hundred forty-four".