1668539546 has 4 divisors (see below), whose sum is σ = 2502809322. Its totient is φ = 834269772.

The previous prime is 1668539513. The next prime is 1668539597. The reversal of 1668539546 is 6459358661.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 958583521 + 709956025 = 30961^2 + 26645^2 .

It is a super-2 number, since 2×1668539546² = 5568048433131772232, which contains 22 as substring.

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 as a sum of consecutive naturals, namely, 417134885 + ... + 417134888.

Almost surely, 2^1668539546 is an apocalyptic number.

1668539546 is a deficient number, since it is larger than the sum of its proper divisors (834269776).

1668539546 is an equidigital number, since it uses as much as digits as its factorization.

1668539546 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 834269775.

The product of its digits is 4665600, while the sum is 53.

The square root of 1668539546 is about 40847.7605995727. The cubic root of 1668539546 is about 1186.0750440454.

The spelling of 1668539546 in words is "one billion, six hundred sixty-eight million, five hundred thirty-nine thousand, five hundred forty-six".