1664542 has 16 divisors (see below), whose sum is σ = 2818800. Its totient is φ = 730240.

The previous prime is 1664501. The next prime is 1664543. The reversal of 1664542 is 2454661.

It is a self number, because there is not a number n which added to its sum of digits gives 1664542.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1664543) 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 7 ways as a sum of consecutive naturals, for example, 667 + ... + 1942.

It is an arithmetic number, because the mean of its divisors is an integer number (176175).

2^1664542 is an apocalyptic number.

1664542 is a deficient number, since it is larger than the sum of its proper divisors (1154258).

1664542 is a wasteful number, since it uses less digits than its factorization.

1664542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2651.

The product of its digits is 5760, while the sum is 28.

The square root of 1664542 is about 1290.1713064551. The cubic root of 1664542 is about 118.5127073081.

The spelling of 1664542 in words is "one million, six hundred sixty-four thousand, five hundred forty-two".