1221111000101 has 4 divisors (see below), whose sum is σ = 1221114701100. Its totient is φ = 1221107299104.

The previous prime is 1221111000089. The next prime is 1221111000107. The reversal of 1221111000101 is 1010001111221.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 812208303076 + 408902697025 = 901226^2 + 639455^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221111000101 - 2²² = 1221106805797 is a prime.

It is a super-2 number, since 2×1221111000101² (a number of 25 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 (1221111000107) 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, 1301246 + ... + 2033583.

It is an arithmetic number, because the mean of its divisors is an integer number (305278675275).

Almost surely, 2^{1221111000101} is an apocalyptic number.

It is an amenable number.

1221111000101 is a deficient number, since it is larger than the sum of its proper divisors (3700999).

1221111000101 is an equidigital number, since it uses as much as digits as its factorization.

1221111000101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3700998.

The product of its (nonzero) digits is 4, while the sum is 11.

Adding to 1221111000101 its reverse (1010001111221), we get a palindrome (2231112111322).

The spelling of 1221111000101 in words is "one trillion, two hundred twenty-one billion, one hundred eleven million, one hundred one", and thus it is an aban number.