51243222166621 has 16 divisors (see below), whose sum is σ = 52121885785200. Its totient is φ = 50371747430400.

The previous prime is 51243222166603. The next prime is 51243222166649. The reversal of 51243222166621 is 12666122234215.

It can be written as a sum of positive squares in 8 ways, for example, as 26184047191225 + 25059174975396 = 5117035^2 + 5005914^2 .

It is a cyclic number.

It is not a de Polignac number, because 51243222166621 - 2¹⁷ = 51243222035549 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 (51243222166121) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 286094325 + ... + 286273381.

It is an arithmetic number, because the mean of its divisors is an integer number (3257617861575).

Almost surely, 2^{51243222166621} is an apocalyptic number.

It is an amenable number.

51243222166621 is a deficient number, since it is larger than the sum of its proper divisors (878663618579).

51243222166621 is a wasteful number, since it uses less digits than its factorization.

51243222166621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 199104.

The product of its digits is 414720, while the sum is 43.

The spelling of 51243222166621 in words is "fifty-one trillion, two hundred forty-three billion, two hundred twenty-two million, one hundred sixty-six thousand, six hundred twenty-one".