651221666141 has 4 divisors (see below), whose sum is σ = 655592281500. Its totient is φ = 646851050784.

The previous prime is 651221666113. The next prime is 651221666171. The reversal of 651221666141 is 141666122156.

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 167600172100 + 483621494041 = 409390^2 + 695429^2 .

It is a cyclic number.

It is not a de Polignac number, because 651221666141 - 2³⁰ = 650147924317 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (651221666171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2185307456 + ... + 2185307753.

It is an arithmetic number, because the mean of its divisors is an integer number (163898070375).

Almost surely, 2^651221666141 is an apocalyptic number.

It is an amenable number.

651221666141 is a deficient number, since it is larger than the sum of its proper divisors (4370615359).

651221666141 is a wasteful number, since it uses less digits than its factorization.

651221666141 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4370615358.

The product of its digits is 103680, while the sum is 41.

Adding to 651221666141 its reverse (141666122156), we get a palindrome (792887788297).

The spelling of 651221666141 in words is "six hundred fifty-one billion, two hundred twenty-one million, six hundred sixty-six thousand, one hundred forty-one".