3939421 has 2 divisors, whose sum is σ = 3939422. Its totient is φ = 3939420.

The previous prime is 3939379. The next prime is 3939433. The reversal of 3939421 is 1249393.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3463321 + 476100 = 1861^2 + 690^2 .

It is a cyclic number.

It is not a de Polignac number, because 3939421 - 2¹⁵ = 3906653 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3939521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1969710 + 1969711.

It is an arithmetic number, because the mean of its divisors is an integer number (1969711).

Almost surely, 2^3939421 is an apocalyptic number.

It is an amenable number.

3939421 is a deficient number, since it is larger than the sum of its proper divisors (1).

3939421 is an equidigital number, since it uses as much as digits as its factorization.

3939421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5832, while the sum is 31.

The square root of 3939421 is about 1984.7974707763. The cubic root of 3939421 is about 157.9346656114.

The spelling of 3939421 in words is "three million, nine hundred thirty-nine thousand, four hundred twenty-one".