3561921 has 32 divisors (see below), whose sum is σ = 5875200. Its totient is φ = 2114640.

The previous prime is 3561913. The next prime is 3561947. The reversal of 3561921 is 1291653.

3561921 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 3561921 - 2³ = 3561913 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (3561221) 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 31 ways as a sum of consecutive naturals, for example, 19810 + ... + 19988.

It is an arithmetic number, because the mean of its divisors is an integer number (183600).

Almost surely, 2^3561921 is an apocalyptic number.

It is an amenable number.

3561921 is a deficient number, since it is larger than the sum of its proper divisors (2313279).

3561921 is a wasteful number, since it uses less digits than its factorization.

3561921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 266 (or 260 counting only the distinct ones).

The product of its digits is 1620, while the sum is 27.

The square root of 3561921 is about 1887.3052217381. The cubic root of 3561921 is about 152.7195940597.

The spelling of 3561921 in words is "three million, five hundred sixty-one thousand, nine hundred twenty-one".