1668533407 has 4 divisors (see below), whose sum is σ = 1677269376. Its totient is φ = 1659797440.

The previous prime is 1668533381. The next prime is 1668533437. The reversal of 1668533407 is 7043358661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7043358661 = 3137 ⋅2245253.

It is a cyclic number.

It is not a de Polignac number, because 1668533407 - 2²³ = 1660144799 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1668533437) 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 in 3 ways as a sum of consecutive naturals, for example, 4367698 + ... + 4368079.

It is an arithmetic number, because the mean of its divisors is an integer number (419317344).

Almost surely, 2^1668533407 is an apocalyptic number.

1668533407 is a deficient number, since it is larger than the sum of its proper divisors (8735969).

1668533407 is an equidigital number, since it uses as much as digits as its factorization.

1668533407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8735968.

The product of its (nonzero) digits is 362880, while the sum is 43.

The square root of 1668533407 is about 40847.6854546252. The cubic root of 1668533407 is about 1186.0735894153.

The spelling of 1668533407 in words is "one billion, six hundred sixty-eight million, five hundred thirty-three thousand, four hundred seven".