1664042020 has 24 divisors (see below), whose sum is σ = 3514694904. Its totient is φ = 661767936.

The previous prime is 1664041999. The next prime is 1664042047. The reversal of 1664042020 is 202404661.

It can be written as a sum of positive squares in 4 ways, for example, as 589906944 + 1074135076 = 24288^2 + 32774^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 237009 + ... + 243928.

It is an arithmetic number, because the mean of its divisors is an integer number (146445621).

Almost surely, 2^1664042020 is an apocalyptic number.

1664042020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1664042020 is an abundant number, since it is smaller than the sum of its proper divisors (1850652884).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1664042020 is a wasteful number, since it uses less digits than its factorization.

1664042020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 481119 (or 481117 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 1664042020 is about 40792.6711554907. The cubic root of 1664042020 is about 1185.0084019653.

Adding to 1664042020 its reverse (202404661), we get a palindrome (1866446681).

The spelling of 1664042020 in words is "one billion, six hundred sixty-four million, forty-two thousand, twenty".