1664000643 has 8 divisors (see below), whose sum is σ = 2265873408. Its totient is φ = 1085730824.

The previous prime is 1664000641. The next prime is 1664000669. The reversal of 1664000643 is 3460004661.

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

It is a cyclic number.

It is not a de Polignac number, because 1664000643 - 2¹ = 1664000641 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1664000643.

It is not an unprimeable number, because it can be changed into a prime (1664000641) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5900571 + ... + 5900852.

It is an arithmetic number, because the mean of its divisors is an integer number (283234176).

Almost surely, 2^1664000643 is an apocalyptic number.

1664000643 is a deficient number, since it is larger than the sum of its proper divisors (601872765).

1664000643 is a wasteful number, since it uses less digits than its factorization.

1664000643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11801473.

The product of its (nonzero) digits is 10368, while the sum is 30.

The square root of 1664000643 is about 40792.1639901587. The cubic root of 1664000643 is about 1184.9985799979.

The spelling of 1664000643 in words is "one billion, six hundred sixty-four million, six hundred forty-three", and thus it is an aban number.