3915421 has 2 divisors, whose sum is σ = 3915422. Its totient is φ = 3915420.

The previous prime is 3915419. The next prime is 3915427. The reversal of 3915421 is 1245193.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3080025 + 835396 = 1755^2 + 914^2 .

It is a cyclic number.

It is not a de Polignac number, because 3915421 - 2¹ = 3915419 is a prime.

Together with 3915419, 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 (3915427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1957710 + 1957711.

It is an arithmetic number, because the mean of its divisors is an integer number (1957711).

Almost surely, 2^3915421 is an apocalyptic number.

It is an amenable number.

3915421 is a deficient number, since it is larger than the sum of its proper divisors (1).

3915421 is an equidigital number, since it uses as much as digits as its factorization.

3915421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1080, while the sum is 25.

The square root of 3915421 is about 1978.7422773065. The cubic root of 3915421 is about 157.6132854244.

The spelling of 3915421 in words is "three million, nine hundred fifteen thousand, four hundred twenty-one".