1664738500 has 24 divisors (see below), whose sum is σ = 3635789976. Its totient is φ = 665895200.

The previous prime is 1664738489. The next prime is 1664738531. The reversal of 1664738500 is 58374661.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 50466816 + 1614271684 = 7104^2 + 40178^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1664239 + ... + 1665238.

It is an arithmetic number, because the mean of its divisors is an integer number (151491249).

Almost surely, 2^1664738500 is an apocalyptic number.

1664738500 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1664738500 is an abundant number, since it is smaller than the sum of its proper divisors (1971051476).

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

1664738500 is a wasteful number, since it uses less digits than its factorization.

1664738500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3329496 (or 3329484 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 40.

The square root of 1664738500 is about 40801.2070899869. The cubic root of 1664738500 is about 1185.1737061907.

The spelling of 1664738500 in words is "one billion, six hundred sixty-four million, seven hundred thirty-eight thousand, five hundred".