3919561 has 4 divisors (see below), whose sum is σ = 3926932. Its totient is φ = 3912192.

The previous prime is 3919549. The next prime is 3919577. The reversal of 3919561 is 1659193.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1659193 = 233 ⋅7121.

It can be written as a sum of positive squares in 2 ways, for example, as 2433600 + 1485961 = 1560^2 + 1219^2 .

It is a cyclic number.

It is not a de Polignac number, because 3919561 - 2⁹ = 3919049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3919501) 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, 2820 + ... + 3973.

It is an arithmetic number, because the mean of its divisors is an integer number (981733).

Almost surely, 2^3919561 is an apocalyptic number.

It is an amenable number.

3919561 is a deficient number, since it is larger than the sum of its proper divisors (7371).

3919561 is an equidigital number, since it uses as much as digits as its factorization.

3919561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7370.

The product of its digits is 7290, while the sum is 34.

The square root of 3919561 is about 1979.7881199765. The cubic root of 3919561 is about 157.6688170564.

It can be divided in two parts, 39 and 19561, that added together give a square (19600 = 140²).

The spelling of 3919561 in words is "three million, nine hundred nineteen thousand, five hundred sixty-one".