3945405 has 16 divisors (see below), whose sum is σ = 6390720. Its totient is φ = 2078208.

The previous prime is 3945391. The next prime is 3945413. The reversal of 3945405 is 5045493.

It is not a de Polignac number, because 3945405 - 2⁶ = 3945341 is a prime.

It is a super-2 number, since 2×3945405² = 31132441228050, which contains 22 as substring.

It is a Curzon number.

3945405 is a lucky number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 340 + ... + 2829.

It is an arithmetic number, because the mean of its divisors is an integer number (399420).

Almost surely, 2^3945405 is an apocalyptic number.

It is an amenable number.

3945405 is a deficient number, since it is larger than the sum of its proper divisors (2445315).

3945405 is a wasteful number, since it uses less digits than its factorization.

3945405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3260.

The product of its (nonzero) digits is 10800, while the sum is 30.

The square root of 3945405 is about 1986.3043573431. The cubic root of 3945405 is about 158.0145930013.

The spelling of 3945405 in words is "three million, nine hundred forty-five thousand, four hundred five".