1664255513 has 4 divisors (see below), whose sum is σ = 1665730740. Its totient is φ = 1662780288.

The previous prime is 1664255441. The next prime is 1664255519. The reversal of 1664255513 is 3155524661.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 790284544 + 873970969 = 28112^2 + 29563^2 .

It is a cyclic number.

It is not a de Polignac number, because 1664255513 - 2²⁴ = 1647478297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1664255519) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 735920 + ... + 738177.

It is an arithmetic number, because the mean of its divisors is an integer number (416432685).

Almost surely, 2^1664255513 is an apocalyptic number.

It is an amenable number.

1664255513 is a deficient number, since it is larger than the sum of its proper divisors (1475227).

1664255513 is a wasteful number, since it uses less digits than its factorization.

1664255513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1475226.

The product of its digits is 108000, while the sum is 38.

The square root of 1664255513 is about 40795.2878774007. The cubic root of 1664255513 is about 1185.0590778050.

The spelling of 1664255513 in words is "one billion, six hundred sixty-four million, two hundred fifty-five thousand, five hundred thirteen".