1668722500 has 135 divisors (see below), whose sum is σ = 3942980811. Its totient is φ = 617652000.

The previous prime is 1668722483. The next prime is 1668722579. The reversal of 1668722500 is 52278661.

It is a happy number.

The square root of 1668722500 is 40850.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 2 ways, for example, as 130827844 + 1537894656 = 11438^2 + 39216^2 .

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1668722500.

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 44 ways as a sum of consecutive naturals, for example, 38807479 + ... + 38807521.

Almost surely, 2^1668722500 is an apocalyptic number.

1668722500 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1668722500 is the 40850-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1668722500

1668722500 is an abundant number, since it is smaller than the sum of its proper divisors (2274258311).

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

1668722500 is an equidigital number, since it uses as much as digits as its factorization.

1668722500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148 (or 69 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 37.

The cubic root of 1668722500 is about 1186.1183931814.

The spelling of 1668722500 in words is "one billion, six hundred sixty-eight million, seven hundred twenty-two thousand, five hundred".