4006385 has 4 divisors (see below), whose sum is σ = 4807668. Its totient is φ = 3205104.

The previous prime is 4006381. The next prime is 4006403. The reversal of 4006385 is 5836004.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2876416 + 1129969 = 1696^2 + 1063^2 .

It is a cyclic number.

It is not a de Polignac number, because 4006385 - 2² = 4006381 is a prime.

It is a super-2 number, since 2×4006385² = 32102241536450, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (4006381) 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, 400634 + ... + 400643.

It is an arithmetic number, because the mean of its divisors is an integer number (1201917).

Almost surely, 2^4006385 is an apocalyptic number.

It is an amenable number.

4006385 is a deficient number, since it is larger than the sum of its proper divisors (801283).

4006385 is an equidigital number, since it uses as much as digits as its factorization.

4006385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 801282.

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 4006385 is about 2001.5956135044. The cubic root of 4006385 is about 158.8245232596.

The spelling of 4006385 in words is "four million, six thousand, three hundred eighty-five".