664530091 has 8 divisors (see below), whose sum is σ = 681076368. Its totient is φ = 648000000.

The previous prime is 664530089. The next prime is 664530103. The reversal of 664530091 is 190035466.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a 9-Lehmer number, since φ(664530091) divides (664530091-1)⁹.

It is a cyclic number.

It is not a de Polignac number, because 664530091 - 2¹ = 664530089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (664030091) 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 7 ways as a sum of consecutive naturals, for example, 162016 + ... + 166066.

It is an arithmetic number, because the mean of its divisors is an integer number (85134546).

Almost surely, 2^664530091 is an apocalyptic number.

664530091 is a deficient number, since it is larger than the sum of its proper divisors (16546277).

664530091 is a wasteful number, since it uses less digits than its factorization.

664530091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8093.

The product of its (nonzero) digits is 19440, while the sum is 34.

The square root of 664530091 is about 25778.4811616201. The cubic root of 664530091 is about 872.6462306115.

The spelling of 664530091 in words is "six hundred sixty-four million, five hundred thirty thousand, ninety-one".