100199617216561 has 2 divisors, whose sum is σ = 100199617216562. Its totient is φ = 100199617216560.

The previous prime is 100199617216537. The next prime is 100199617216631. The reversal of 100199617216561 is 165612716991001.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 97345355640625 + 2854261575936 = 9866375^2 + 1689456^2 .

It is a cyclic number.

It is not a de Polignac number, because 100199617216561 - 2¹⁵ = 100199617183793 is a prime.

It is a super-2 number, since 2×100199617216561² (a number of 29 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (100199617216861) 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 as a sum of consecutive naturals, namely, 50099808608280 + 50099808608281.

It is an arithmetic number, because the mean of its divisors is an integer number (50099808608281).

Almost surely, 2^{100199617216561} is an apocalyptic number.

It is an amenable number.

100199617216561 is a deficient number, since it is larger than the sum of its proper divisors (1).

100199617216561 is an equidigital number, since it uses as much as digits as its factorization.

100199617216561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1224720, while the sum is 55.

The spelling of 100199617216561 in words is "one hundred trillion, one hundred ninety-nine billion, six hundred seventeen million, two hundred sixteen thousand, five hundred sixty-one".