1968661 has 4 divisors (see below), whose sum is σ = 1998112. Its totient is φ = 1939212.

The previous prime is 1968641. The next prime is 1968679. The reversal of 1968661 is 1668691.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1668691 = 97 ⋅17203.

It is a cyclic number.

It is not a de Polignac number, because 1968661 - 2⁹ = 1968149 is a prime.

It is a super-2 number, since 2×1968661² = 7751252265842, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1968661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1968611) 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, 14625 + ... + 14758.

It is an arithmetic number, because the mean of its divisors is an integer number (499528).

2^1968661 is an apocalyptic number.

It is an amenable number.

1968661 is a deficient number, since it is larger than the sum of its proper divisors (29451).

1968661 is an equidigital number, since it uses as much as digits as its factorization.

1968661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29450.

The product of its digits is 15552, while the sum is 37.

The square root of 1968661 is about 1403.0898046811. The cubic root of 1968661 is about 125.3305597382.

The spelling of 1968661 in words is "one million, nine hundred sixty-eight thousand, six hundred sixty-one".