3921217 has 2 divisors, whose sum is σ = 3921218. Its totient is φ = 3921216.

The previous prime is 3921209. The next prime is 3921227. The reversal of 3921217 is 7121293.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3904576 + 16641 = 1976^2 + 129^2 .

It is a cyclic number.

It is not a de Polignac number, because 3921217 - 2³ = 3921209 is a prime.

It is a super-2 number, since 2×3921217² = 30751885522178, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 3921191 and 3921200.

It is not a weakly prime, because it can be changed into another prime (3921227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1960608 + 1960609.

It is an arithmetic number, because the mean of its divisors is an integer number (1960609).

Almost surely, 2^3921217 is an apocalyptic number.

It is an amenable number.

3921217 is a deficient number, since it is larger than the sum of its proper divisors (1).

3921217 is an equidigital number, since it uses as much as digits as its factorization.

3921217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 756, while the sum is 25.

The square root of 3921217 is about 1980.2063023837. The cubic root of 3921217 is about 157.6910187603.

The spelling of 3921217 in words is "three million, nine hundred twenty-one thousand, two hundred seventeen".