1613561 has 4 divisors (see below), whose sum is σ = 1637712. Its totient is φ = 1589412.

The previous prime is 1613543. The next prime is 1613587. The reversal of 1613561 is 1653161.

It is a happy number.

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.

It is a cyclic number.

It is not a de Polignac number, because 1613561 - 2⁶ = 1613497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1613761) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11975 + ... + 12108.

It is an arithmetic number, because the mean of its divisors is an integer number (409428).

2^1613561 is an apocalyptic number.

It is an amenable number.

1613561 is a deficient number, since it is larger than the sum of its proper divisors (24151).

1613561 is an equidigital number, since it uses as much as digits as its factorization.

1613561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24150.

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

The square root of 1613561 is about 1270.2602095634. The cubic root of 1613561 is about 117.2902187136.

The spelling of 1613561 in words is "one million, six hundred thirteen thousand, five hundred sixty-one".