1201220001001 has 4 divisors (see below), whose sum is σ = 1201243638100. Its totient is φ = 1201196363904.

The previous prime is 1201220000999. The next prime is 1201220001067. The reversal of 1201220001001 is 1001000221021.

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 494651989225 + 706568011776 = 703315^2 + 840576^2 .

It is a cyclic number.

It is not a de Polignac number, because 1201220001001 - 2¹ = 1201220000999 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1201220001601) 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, 11742156 + ... + 11844013.

It is an arithmetic number, because the mean of its divisors is an integer number (300310909525).

Almost surely, 2^{1201220001001} is an apocalyptic number.

It is an amenable number.

1201220001001 is a deficient number, since it is larger than the sum of its proper divisors (23637099).

1201220001001 is an equidigital number, since it uses as much as digits as its factorization.

1201220001001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23637098.

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 1201220001001 its reverse (1001000221021), we get a palindrome (2202220222022).

The spelling of 1201220001001 in words is "one trillion, two hundred one billion, two hundred twenty million, one thousand, one".