3561861 has 4 divisors (see below), whose sum is σ = 4749152. Its totient is φ = 2374572.

The previous prime is 3561853. The next prime is 3561881. The reversal of 3561861 is 1681653.

3561861 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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: 1681653 = 3 ⋅560551.

It is not a de Polignac number, because 3561861 - 2³ = 3561853 is a prime.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3561841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 593641 + ... + 593646.

It is an arithmetic number, because the mean of its divisors is an integer number (1187288).

Almost surely, 2^3561861 is an apocalyptic number.

It is an amenable number.

3561861 is a deficient number, since it is larger than the sum of its proper divisors (1187291).

3561861 is a wasteful number, since it uses less digits than its factorization.

3561861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1187290.

The product of its digits is 4320, while the sum is 30.

The square root of 3561861 is about 1887.2893259911. The cubic root of 3561861 is about 152.7187365423.

The spelling of 3561861 in words is "three million, five hundred sixty-one thousand, eight hundred sixty-one".