391716 has 72 divisors (see below), whose sum is σ = 1141504. Its totient is φ = 116640.

The previous prime is 391711. The next prime is 391717. The reversal of 391716 is 617193.

It is a Smith number, since the sum of its digits (27) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

Its product of digits (1134) is a multiple of the sum of its prime factors (63).

It is a self number, because there is not a number n which added to its sum of digits gives 391716.

It is not an unprimeable number, because it can be changed into a prime (391711) by changing a digit.

391716 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12621 + ... + 12651.

2³⁹¹⁷¹⁶ is an apocalyptic number.

391716 is a gapful number since it is divisible by the number (36) 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 391716, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (570752).

391716 is an abundant number, since it is smaller than the sum of its proper divisors (749788).

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

391716 is a wasteful number, since it uses less digits than its factorization.

391716 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63 (or 49 counting only the distinct ones).

The product of its digits is 1134, while the sum is 27.

The square root of 391716 is about 625.8721914257. The cubic root of 391716 is about 73.1684357328.

It can be divided in two parts, 3 and 91716, that added together give a palindrome (91719).

The spelling of 391716 in words is "three hundred ninety-one thousand, seven hundred sixteen".