4391681 has 4 divisors (see below), whose sum is σ = 5019072. Its totient is φ = 3764292.

The previous prime is 4391671. The next prime is 4391683. The reversal of 4391681 is 1861934.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 4391681 - 2⁶ = 4391617 is a prime.

It is a super-2 number, since 2×4391681² = 38573724011522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (4391683) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 313685 + ... + 313698.

It is an arithmetic number, because the mean of its divisors is an integer number (1254768).

Almost surely, 2^4391681 is an apocalyptic number.

It is an amenable number.

4391681 is a deficient number, since it is larger than the sum of its proper divisors (627391).

4391681 is an equidigital number, since it uses as much as digits as its factorization.

4391681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 627390.

The product of its digits is 5184, while the sum is 32.

The square root of 4391681 is about 2095.6337943448. The cubic root of 4391681 is about 163.7609172451.

The spelling of 4391681 in words is "four million, three hundred ninety-one thousand, six hundred eighty-one".