1668611026 has 4 divisors (see below), whose sum is σ = 2502916542. Its totient is φ = 834305512.

The previous prime is 1668611023. The next prime is 1668611033. The reversal of 1668611026 is 6201168661.

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., 1295928001 + 372683025 = 35999^2 + 19305^2 .

It is not an unprimeable number, because it can be changed into a prime (1668611023) by changing a digit.

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 as a sum of consecutive naturals, namely, 417152755 + ... + 417152758.

Almost surely, 2^1668611026 is an apocalyptic number.

1668611026 is a deficient number, since it is larger than the sum of its proper divisors (834305516).

1668611026 is an equidigital number, since it uses as much as digits as its factorization.

1668611026 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 834305515.

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 1668611026 is about 40848.6355463680. The cubic root of 1668611026 is about 1186.0919808997.

Adding to 1668611026 its reverse (6201168661), we get a palindrome (7869779687).

The spelling of 1668611026 in words is "one billion, six hundred sixty-eight million, six hundred eleven thousand, twenty-six".