1641252203665 has 8 divisors (see below), whose sum is σ = 1977166080360. Its totient is φ = 1307892805632.

The previous prime is 1641252203653. The next prime is 1641252203681. The reversal of 1641252203665 is 5663022521461.

It can be written as a sum of positive squares in 4 ways, for example, as 331765632081 + 1309486571584 = 575991^2 + 1144328^2 .

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 1641252203665 - 2³⁹ = 1091496389777 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 638618250 + ... + 638620819.

It is an arithmetic number, because the mean of its divisors is an integer number (247145760045).

Almost surely, 2^{1641252203665} is an apocalyptic number.

It is an amenable number.

1641252203665 is a deficient number, since it is larger than the sum of its proper divisors (335913876695).

1641252203665 is a wasteful number, since it uses less digits than its factorization.

1641252203665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1277239331.

The product of its (nonzero) digits is 518400, while the sum is 43.

The spelling of 1641252203665 in words is "one trillion, six hundred forty-one billion, two hundred fifty-two million, two hundred three thousand, six hundred sixty-five".