1668031601 has 4 divisors (see below), whose sum is σ = 1721839104. Its totient is φ = 1614224100.

The previous prime is 1668031597. The next prime is 1668031637. The reversal of 1668031601 is 1061308661.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1061308661 = 7 ⋅151615523.

It is a cyclic number.

It is not a de Polignac number, because 1668031601 - 2² = 1668031597 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1668031501) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26903705 + ... + 26903766.

It is an arithmetic number, because the mean of its divisors is an integer number (430459776).

Almost surely, 2^1668031601 is an apocalyptic number.

It is an amenable number.

1668031601 is a deficient number, since it is larger than the sum of its proper divisors (53807503).

1668031601 is an equidigital number, since it uses as much as digits as its factorization.

1668031601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53807502.

The product of its (nonzero) digits is 5184, while the sum is 32.

The square root of 1668031601 is about 40841.5425883989. The cubic root of 1668031601 is about 1185.9546749009.

The spelling of 1668031601 in words is "one billion, six hundred sixty-eight million, thirty-one thousand, six hundred one".