512721322561 has 4 divisors (see below), whose sum is σ = 585967225792. Its totient is φ = 439475419332.

The previous prime is 512721322507. The next prime is 512721322579. The reversal of 512721322561 is 165223127215.

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, and also an emirpimes, since its reverse is a distinct semiprime: 165223127215 = 5 ⋅33044625443.

It is a cyclic number.

It is not a de Polignac number, because 512721322561 - 2²⁵ = 512687768129 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 512721322561.

It is not an unprimeable number, because it can be changed into a prime (512821322561) 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, 36622951605 + ... + 36622951618.

It is an arithmetic number, because the mean of its divisors is an integer number (146491806448).

Almost surely, 2^512721322561 is an apocalyptic number.

It is an amenable number.

512721322561 is a deficient number, since it is larger than the sum of its proper divisors (73245903231).

512721322561 is an equidigital number, since it uses as much as digits as its factorization.

512721322561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73245903230.

The product of its digits is 50400, while the sum is 37.

Adding to 512721322561 its reverse (165223127215), we get a palindrome (677944449776).

The spelling of 512721322561 in words is "five hundred twelve billion, seven hundred twenty-one million, three hundred twenty-two thousand, five hundred sixty-one".