391671072 has 96 divisors (see below), whose sum is σ = 1230284160. Its totient is φ = 120510720.

The previous prime is 391671053. The next prime is 391671083. The reversal of 391671072 is 270176193.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (96).

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6204 + ... + 28667.

It is an arithmetic number, because the mean of its divisors is an integer number (12815460).

Almost surely, 2^391671072 is an apocalyptic number.

391671072 is a gapful number since it is divisible by the number (32) 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 391671072, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (615142080).

391671072 is an abundant number, since it is smaller than the sum of its proper divisors (838613088).

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

391671072 is a wasteful number, since it uses less digits than its factorization.

391671072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34903 (or 34889 counting only the distinct ones).

The product of its (nonzero) digits is 15876, while the sum is 36.

The square root of 391671072 is about 19790.6814435481. The cubic root of 391671072 is about 731.6563826633.

The spelling of 391671072 in words is "three hundred ninety-one million, six hundred seventy-one thousand, seventy-two".