1668273620 has 24 divisors (see below), whose sum is σ = 3772865544. Its totient is φ = 615977856.

The previous prime is 1668273619. The next prime is 1668273637. The reversal of 1668273620 is 263728661.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 35952016 + 1632321604 = 5996^2 + 40402^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3207959 + ... + 3208478.

It is an arithmetic number, because the mean of its divisors is an integer number (157202731).

Almost surely, 2^1668273620 is an apocalyptic number.

1668273620 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1668273620 is an abundant number, since it is smaller than the sum of its proper divisors (2104591924).

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

1668273620 is a wasteful number, since it uses less digits than its factorization.

1668273620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6416459 (or 6416457 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 41.

The square root of 1668273620 is about 40844.5053832214. The cubic root of 1668273620 is about 1186.0120298662.

The spelling of 1668273620 in words is "one billion, six hundred sixty-eight million, two hundred seventy-three thousand, six hundred twenty".