1664111 has 4 divisors (see below), whose sum is σ = 1717824. Its totient is φ = 1610400.

The previous prime is 1664101. The next prime is 1664123. The reversal of 1664111 is 1114661.

1664111 = T₂₀₀ + T₂₀₁ + ... + T₂₆₁.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1664111 - 2¹⁴ = 1647727 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1664101) 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, 26810 + ... + 26871.

It is an arithmetic number, because the mean of its divisors is an integer number (429456).

2^1664111 is an apocalyptic number.

1664111 is a deficient number, since it is larger than the sum of its proper divisors (53713).

1664111 is an equidigital number, since it uses as much as digits as its factorization.

1664111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53712.

The product of its digits is 144, while the sum is 20.

The square root of 1664111 is about 1290.0042635588. The cubic root of 1664111 is about 118.5024775901.

Adding to 1664111 its reverse (1114661), we get a palindrome (2778772).

The spelling of 1664111 in words is "one million, six hundred sixty-four thousand, one hundred eleven".