1664055 has 12 divisors (see below), whose sum is σ = 2884440. Its totient is φ = 887472.

The previous prime is 1664053. The next prime is 1664063. The reversal of 1664055 is 5504661.

It is a happy number.

1664055 is a `hidden beast` number, since 16 + 640 + 5 + 5 = 666.

It is not a de Polignac number, because 1664055 - 2¹ = 1664053 is a prime.

1664055 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1664053) 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, 18445 + ... + 18534.

It is an arithmetic number, because the mean of its divisors is an integer number (240370).

2^1664055 is an apocalyptic number.

1664055 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1664055 is a deficient number, since it is larger than the sum of its proper divisors (1220385).

1664055 is a wasteful number, since it uses less digits than its factorization.

1664055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36990 (or 36987 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

The square root of 1664055 is about 1289.9825580216. The cubic root of 1664055 is about 118.5011483091.

Subtracting 1664055 from its reverse (5504661), we obtain a triangular number (3840606 = T₂₇₇₁).

The spelling of 1664055 in words is "one million, six hundred sixty-four thousand, fifty-five".