1664028073 has 4 divisors (see below), whose sum is σ = 1684076688. Its totient is φ = 1643979460.

The previous prime is 1664028029. The next prime is 1664028077. The reversal of 1664028073 is 3708204661.

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.

It is a cyclic number.

It is not a de Polignac number, because 1664028073 - 2¹³ = 1664019881 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1664028077) 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, 10024183 + ... + 10024348.

It is an arithmetic number, because the mean of its divisors is an integer number (421019172).

Almost surely, 2^1664028073 is an apocalyptic number.

It is an amenable number.

1664028073 is a deficient number, since it is larger than the sum of its proper divisors (20048615).

1664028073 is an equidigital number, since it uses as much as digits as its factorization.

1664028073 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20048614.

The product of its (nonzero) digits is 48384, while the sum is 37.

The square root of 1664028073 is about 40792.5002053073. The cubic root of 1664028073 is about 1185.0050912800.

The spelling of 1664028073 in words is "one billion, six hundred sixty-four million, twenty-eight thousand, seventy-three".