391855968 has 288 divisors, whose sum is σ = 1382524416. Its totient is φ = 106748928.

The previous prime is 391855963. The next prime is 391855969. The reversal of 391855968 is 869558193.

It is a happy number.

391855968 is a `hidden beast` number, since 39 + 18 + 5 + 596 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (391855963) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1251780 + ... + 1252092.

It is an arithmetic number, because the mean of its divisors is an integer number (4800432).

Almost surely, 2^391855968 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 391855968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (691262208).

391855968 is an abundant number, since it is smaller than the sum of its proper divisors (990668448).

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

391855968 is a wasteful number, since it uses less digits than its factorization.

391855968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 368 (or 348 counting only the distinct ones).

The product of its digits is 2332800, while the sum is 54.

The square root of 391855968 is about 19795.3521817623. The cubic root of 391855968 is about 731.7714954595.

The spelling of 391855968 in words is "three hundred ninety-one million, eight hundred fifty-five thousand, nine hundred sixty-eight".