3905842 has 4 divisors (see below), whose sum is σ = 5858766. Its totient is φ = 1952920.

The previous prime is 3905833. The next prime is 3905843. The reversal of 3905842 is 2485093.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 2485093 = 13 ⋅191161.

It can be written as a sum of positive squares in only one way, i.e., 3024121 + 881721 = 1739^2 + 939^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (3905843) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 976459 + ... + 976462.

Almost surely, 2^3905842 is an apocalyptic number.

3905842 is a deficient number, since it is larger than the sum of its proper divisors (1952924).

3905842 is a wasteful number, since it uses less digits than its factorization.

3905842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1952923.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 3905842 is about 1976.3203181671. The cubic root of 3905842 is about 157.4846478695.

The spelling of 3905842 in words is "three million, nine hundred five thousand, eight hundred forty-two".