1664271 has 12 divisors (see below), whose sum is σ = 2747472. Its totient is φ = 950976.

The previous prime is 1664261. The next prime is 1664279. The reversal of 1664271 is 1724661.

1664271 is a `hidden beast` number, since 16 + 642 + 7 + 1 = 666.

It is not a de Polignac number, because 1664271 - 2¹¹ = 1662223 is a prime.

It is a super-2 number, since 2×1664271² = 5539595922882, which contains 22 as substring.

1664271 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1664279) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13146 + ... + 13271.

It is an arithmetic number, because the mean of its divisors is an integer number (228956).

2^1664271 is an apocalyptic number.

1664271 is a deficient number, since it is larger than the sum of its proper divisors (1083201).

1664271 is a wasteful number, since it uses less digits than its factorization.

1664271 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26430 (or 26427 counting only the distinct ones).

The product of its digits is 2016, while the sum is 27.

The square root of 1664271 is about 1290.0662773672. The cubic root of 1664271 is about 118.5062753714.

The spelling of 1664271 in words is "one million, six hundred sixty-four thousand, two hundred seventy-one".