1201111100001 has 6 divisors (see below), whose sum is σ = 1734938255570. Its totient is φ = 800740733328.

The previous prime is 1201111099999. The next prime is 1201111100017. The reversal of 1201111100001 is 1000011111021.

It can be written as a sum of positive squares in only one way, i.e., 779194598400 + 421916501601 = 882720^2 + 649551^2 .

It is not a de Polignac number, because 1201111100001 - 2¹ = 1201111099999 is a prime.

It is a super-2 number, since 2×1201111100001² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (9), and also a Moran number because the ratio is a prime number: 133456788889 = 1201111100001 / (1 + 2 + 0 + 1 + 1 + 1 + 1 + 1 + 0 + 0 + 0 + 0 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1201111100051) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 66728394436 + ... + 66728394453.

Almost surely, 2^{1201111100001} is an apocalyptic number.

It is an amenable number.

1201111100001 is a deficient number, since it is larger than the sum of its proper divisors (533827155569).

1201111100001 is a wasteful number, since it uses less digits than its factorization.

1201111100001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133456788895 (or 133456788892 counting only the distinct ones).

The product of its (nonzero) digits is 2, while the sum is 9.

Adding to 1201111100001 its reverse (1000011111021), we get a palindrome (2201122211022).

The spelling of 1201111100001 in words is "one trillion, two hundred one billion, one hundred eleven million, one hundred thousand, one".