100561121 has 4 divisors (see below), whose sum is σ = 100648752. Its totient is φ = 100473492.

The previous prime is 100561099. The next prime is 100561147. The reversal of 100561121 is 121165001.

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, and also an emirpimes, since its reverse is a distinct semiprime: 121165001 = 17 ⋅7127353.

It is a cyclic number.

It is not a de Polignac number, because 100561121 - 2²⁶ = 33452257 is a prime.

It is a super-2 number, since 2×100561121² = 20225078113553282, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 100561121.

It is not an unprimeable number, because it can be changed into a prime (100561421) 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, 42071 + ... + 44396.

It is an arithmetic number, because the mean of its divisors is an integer number (25162188).

Almost surely, 2^100561121 is an apocalyptic number.

It is an amenable number.

100561121 is a deficient number, since it is larger than the sum of its proper divisors (87631).

100561121 is an equidigital number, since it uses as much as digits as its factorization.

100561121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87630.

The product of its (nonzero) digits is 60, while the sum is 17.

The square root of 100561121 is about 10028.0168029377. The cubic root of 100561121 is about 465.0254289096.

It can be divided in two parts, 1005 and 61121, that added together give a palindrome (62126).

The spelling of 100561121 in words is "one hundred million, five hundred sixty-one thousand, one hundred twenty-one".