1664337820 has 12 divisors (see below), whose sum is σ = 3495109464. Its totient is φ = 665735120.

The previous prime is 1664337803. The next prime is 1664337863. The reversal of 1664337820 is 287334661.

It is a zygodrome in base 2.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 41608426 + ... + 41608465.

It is an arithmetic number, because the mean of its divisors is an integer number (291259122).

Almost surely, 2^1664337820 is an apocalyptic number.

1664337820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1664337820 is an abundant number, since it is smaller than the sum of its proper divisors (1830771644).

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

1664337820 is a wasteful number, since it uses less digits than its factorization.

1664337820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83216900 (or 83216898 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 40.

The square root of 1664337820 is about 40796.2966456516. The cubic root of 1664337820 is about 1185.0786134770.

The spelling of 1664337820 in words is "one billion, six hundred sixty-four million, three hundred thirty-seven thousand, eight hundred twenty".