3945217 has 4 divisors (see below), whose sum is σ = 4152880. Its totient is φ = 3737556.

The previous prime is 3945203. The next prime is 3945233. The reversal of 3945217 is 7125493.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 7125493 = 733 ⋅9721.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3945217 is a prime.

It is a Duffinian number.

3945217 is a lucky number.

It is a zygodrome in base 11.

It is not an unprimeable number, because it can be changed into a prime (3945287) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 103803 + ... + 103840.

It is an arithmetic number, because the mean of its divisors is an integer number (1038220).

Almost surely, 2^3945217 is an apocalyptic number.

It is an amenable number.

3945217 is a deficient number, since it is larger than the sum of its proper divisors (207663).

3945217 is a wasteful number, since it uses less digits than its factorization.

3945217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 207662.

The product of its digits is 7560, while the sum is 31.

The square root of 3945217 is about 1986.2570327125. The cubic root of 3945217 is about 158.0120831436.

The spelling of 3945217 in words is "three million, nine hundred forty-five thousand, two hundred seventeen".