1012100001221 has 4 divisors (see below), whose sum is σ = 1014701801100. Its totient is φ = 1009498201344.

The previous prime is 1012100001173. The next prime is 1012100001271. The reversal of 1012100001221 is 1221000012101.

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 449585001121 + 562515000100 = 670511^2 + 750010^2 .

It is a cyclic number.

It is not a de Polignac number, because 1012100001221 - 2³⁸ = 737222094277 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1012100001271) 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, 1300899356 + ... + 1300900133.

It is an arithmetic number, because the mean of its divisors is an integer number (253675450275).

Almost surely, 2^{1012100001221} is an apocalyptic number.

It is an amenable number.

1012100001221 is a deficient number, since it is larger than the sum of its proper divisors (2601799879).

1012100001221 is an equidigital number, since it uses as much as digits as its factorization.

1012100001221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2601799878.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 1012100001221 its reverse (1221000012101), we get a palindrome (2233100013322).

The spelling of 1012100001221 in words is "one trillion, twelve billion, one hundred million, one thousand, two hundred twenty-one".