100561211961 has 48 divisors (see below), whose sum is σ = 162119709696. Its totient is φ = 54302406048.

The previous prime is 100561211917. The next prime is 100561211963. The reversal of 100561211961 is 169112165001.

It is not a de Polignac number, because 100561211961 - 2¹⁵ = 100561179193 is a prime.

It is a super-2 number, since 2×100561211961² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (100561211963) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 867516 + ... + 976578.

It is an arithmetic number, because the mean of its divisors is an integer number (3377493952).

Almost surely, 2^100561211961 is an apocalyptic number.

It is an amenable number.

100561211961 is a deficient number, since it is larger than the sum of its proper divisors (61558497735).

100561211961 is a wasteful number, since it uses less digits than its factorization.

100561211961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109202 (or 109179 counting only the distinct ones).

The product of its (nonzero) digits is 3240, while the sum is 33.

Adding to 100561211961 its reverse (169112165001), we get a palindrome (269673376962).

The spelling of 100561211961 in words is "one hundred billion, five hundred sixty-one million, two hundred eleven thousand, nine hundred sixty-one".