100561165111661 has 4 divisors (see below), whose sum is σ = 100561204212000. Its totient is φ = 100561126011324.

The previous prime is 100561165111643. The next prime is 100561165111681. The reversal of 100561165111661 is 166111561165001.

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.

It is a cyclic number.

It is not a de Polignac number, because 100561165111661 - 2¹⁴ = 100561165095277 is a prime.

It is a super-2 number, since 2×100561165111661² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100561165111681) 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, 15398471 + ... + 20934068.

It is an arithmetic number, because the mean of its divisors is an integer number (25140301053000).

Almost surely, 2^{100561165111661} is an apocalyptic number.

It is an amenable number.

100561165111661 is a deficient number, since it is larger than the sum of its proper divisors (39100339).

100561165111661 is an equidigital number, since it uses as much as digits as its factorization.

100561165111661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39100338.

The product of its (nonzero) digits is 32400, while the sum is 41.

The spelling of 100561165111661 in words is "one hundred trillion, five hundred sixty-one billion, one hundred sixty-five million, one hundred eleven thousand, six hundred sixty-one".