1611861 has 4 divisors (see below), whose sum is σ = 2149152. Its totient is φ = 1074572.

The previous prime is 1611853. The next prime is 1611877. The reversal of 1611861 is 1681161.

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 1611861 - 2³ = 1611853 is a prime.

It is a D-number.

1611861 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1611851) 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, 268641 + ... + 268646.

It is an arithmetic number, because the mean of its divisors is an integer number (537288).

2^1611861 is an apocalyptic number.

It is an amenable number.

1611861 is a deficient number, since it is larger than the sum of its proper divisors (537291).

1611861 is an equidigital number, since it uses as much as digits as its factorization.

1611861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 537290.

The product of its digits is 288, while the sum is 24.

The square root of 1611861 is about 1269.5908789842. The cubic root of 1611861 is about 117.2490130743.

The spelling of 1611861 in words is "one million, six hundred eleven thousand, eight hundred sixty-one".