3663421 has 2 divisors, whose sum is σ = 3663422. Its totient is φ = 3663420.

The previous prime is 3663419. The next prime is 3663427. The reversal of 3663421 is 1243663.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3663396 + 25 = 1914^2 + 5^2 .

It is an emirp because it is prime and its reverse (1243663) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3663421 - 2¹ = 3663419 is a prime.

Together with 3663419, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3663427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1831710 + 1831711.

It is an arithmetic number, because the mean of its divisors is an integer number (1831711).

Almost surely, 2^3663421 is an apocalyptic number.

It is an amenable number.

3663421 is a deficient number, since it is larger than the sum of its proper divisors (1).

3663421 is an equidigital number, since it uses as much as digits as its factorization.

3663421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2592, while the sum is 25.

The square root of 3663421 is about 1914.0065308144. The cubic root of 3663421 is about 154.1566545564.

Subtracting from 3663421 its sum of digits (25), we obtain a square (3663396 = 1914²).

The spelling of 3663421 in words is "three million, six hundred sixty-three thousand, four hundred twenty-one".