1664526205 has 8 divisors (see below), whose sum is σ = 1998886104. Its totient is φ = 1330651200.

The previous prime is 1664526187. The next prime is 1664526223. The reversal of 1664526205 is 5026254661.

It is an interprime number because it is at equal distance from previous prime (1664526187) and next prime (1664526223).

It can be written as a sum of positive squares in 4 ways, for example, as 575328196 + 1089198009 = 23986^2 + 33003^2 .

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

It is not a de Polignac number, because 1664526205 - 2¹³ = 1664518013 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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, 113626 + ... + 127435.

It is an arithmetic number, because the mean of its divisors is an integer number (249860763).

Almost surely, 2^1664526205 is an apocalyptic number.

It is an amenable number.

1664526205 is a deficient number, since it is larger than the sum of its proper divisors (334359899).

1664526205 is a wasteful number, since it uses less digits than its factorization.

1664526205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 242447.

The product of its (nonzero) digits is 86400, while the sum is 37.

The square root of 1664526205 is about 40798.6054295977. The cubic root of 1664526205 is about 1185.1233244744.

The spelling of 1664526205 in words is "one billion, six hundred sixty-four million, five hundred twenty-six thousand, two hundred five".