1591961 has 12 divisors (see below), whose sum is σ = 1889892. Its totient is φ = 1336608.

The previous prime is 1591949. The next prime is 1591969. The reversal of 1591961 is 1691951.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 414736 + 1177225 = 644^2 + 1085^2 .

It is not a de Polignac number, because 1591961 - 2¹⁰ = 1590937 is a prime.

It is a Smith number, since the sum of its digits (32) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1591969) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2291 + ... + 2903.

It is an arithmetic number, because the mean of its divisors is an integer number (157491).

2^1591961 is an apocalyptic number.

It is an amenable number.

1591961 is a deficient number, since it is larger than the sum of its proper divisors (297931).

1591961 is an equidigital number, since it uses as much as digits as its factorization.

1591961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 680 (or 673 counting only the distinct ones).

The product of its digits is 2430, while the sum is 32.

The square root of 1591961 is about 1261.7293687634. The cubic root of 1591961 is about 116.7644957218.

It can be divided in two parts, 1591 and 961, that added together give a palindrome (2552).

The spelling of 1591961 in words is "one million, five hundred ninety-one thousand, nine hundred sixty-one".