1361561 has 4 divisors (see below), whose sum is σ = 1365300. Its totient is φ = 1357824.

The previous prime is 1361533. The next prime is 1361573. The reversal of 1361561 is 1651631.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1651631 = 173 ⋅9547.

It can be written as a sum of positive squares in 2 ways, for example, as 931225 + 430336 = 965^2 + 656^2 .

It is a cyclic number.

It is not a de Polignac number, because 1361561 - 2⁶ = 1361497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1369561) 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, 1256 + ... + 2073.

It is an arithmetic number, because the mean of its divisors is an integer number (341325).

2^1361561 is an apocalyptic number.

It is an amenable number.

1361561 is a deficient number, since it is larger than the sum of its proper divisors (3739).

1361561 is an equidigital number, since it uses as much as digits as its factorization.

1361561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3738.

The product of its digits is 540, while the sum is 23.

The square root of 1361561 is about 1166.8594602607. The cubic root of 1361561 is about 110.8355381751.

The spelling of 1361561 in words is "one million, three hundred sixty-one thousand, five hundred sixty-one".