624642220561 has 4 divisors (see below), whose sum is σ = 661385880612. Its totient is φ = 587898560512.

The previous prime is 624642220421. The next prime is 624642220577. The reversal of 624642220561 is 165022246426.

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 318949339536 + 305692881025 = 564756^2 + 552895^2 .

It is a cyclic number.

It is not a de Polignac number, because 624642220561 - 2¹¹ = 624642218513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (624642220261) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 18371830000 + ... + 18371830033.

It is an arithmetic number, because the mean of its divisors is an integer number (165346470153).

Almost surely, 2^624642220561 is an apocalyptic number.

It is an amenable number.

624642220561 is a deficient number, since it is larger than the sum of its proper divisors (36743660051).

624642220561 is a wasteful number, since it uses less digits than its factorization.

624642220561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36743660050.

The product of its (nonzero) digits is 276480, while the sum is 40.

Adding to 624642220561 its reverse (165022246426), we get a palindrome (789664466987).

The spelling of 624642220561 in words is "six hundred twenty-four billion, six hundred forty-two million, two hundred twenty thousand, five hundred sixty-one".