3940643 has 4 divisors (see below), whose sum is σ = 4503600. Its totient is φ = 3377688.

The previous prime is 3940637. The next prime is 3940663. The reversal of 3940643 is 3460493.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3460493 = 733 ⋅4721.

It is a cyclic number.

It is not a de Polignac number, because 3940643 - 2⁶ = 3940579 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3940663) 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, 281468 + ... + 281481.

It is an arithmetic number, because the mean of its divisors is an integer number (1125900).

Almost surely, 2^3940643 is an apocalyptic number.

3940643 is a deficient number, since it is larger than the sum of its proper divisors (562957).

3940643 is an equidigital number, since it uses as much as digits as its factorization.

3940643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 562956.

The product of its (nonzero) digits is 7776, while the sum is 29.

The square root of 3940643 is about 1985.1052868803. The cubic root of 3940643 is about 157.9509942554.

The spelling of 3940643 in words is "three million, nine hundred forty thousand, six hundred forty-three".