3994621 has 2 divisors, whose sum is σ = 3994622. Its totient is φ = 3994620.

The previous prime is 3994619. The next prime is 3994681. The reversal of 3994621 is 1264993.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2528100 + 1466521 = 1590^2 + 1211^2 .

It is a cyclic number.

It is not a de Polignac number, because 3994621 - 2¹ = 3994619 is a prime.

Together with 3994619, it forms a pair of twin primes.

3994621 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3994681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1997310 + 1997311.

It is an arithmetic number, because the mean of its divisors is an integer number (1997311).

Almost surely, 2^3994621 is an apocalyptic number.

It is an amenable number.

3994621 is a deficient number, since it is larger than the sum of its proper divisors (1).

3994621 is an equidigital number, since it uses as much as digits as its factorization.

3994621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11664, while the sum is 34.

The square root of 3994621 is about 1998.6547976076. The cubic root of 3994621 is about 158.6689180255.

The spelling of 3994621 in words is "three million, nine hundred ninety-four thousand, six hundred twenty-one".