1221110020001 has 8 divisors (see below), whose sum is σ = 1264440155880. Its totient is φ = 1177861410432.

The previous prime is 1221110019991. The next prime is 1221110020093. The reversal of 1221110020001 is 1000200111221.

It can be written as a sum of positive squares in 4 ways, for example, as 650359989601 + 570750030400 = 806449^2 + 755480^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1221110020001 - 2¹⁰ = 1221110018977 is a prime.

It is a super-2 number, since 2×1221110020001² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221110020301) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20351090 + ... + 20411003.

It is an arithmetic number, because the mean of its divisors is an integer number (158055019485).

Almost surely, 2^{1221110020001} is an apocalyptic number.

It is an amenable number.

1221110020001 is a deficient number, since it is larger than the sum of its proper divisors (43330135879).

1221110020001 is a wasteful number, since it uses less digits than its factorization.

1221110020001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40763155.

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

Adding to 1221110020001 its reverse (1000200111221), we get a palindrome (2221310131222).

The spelling of 1221110020001 in words is "one trillion, two hundred twenty-one billion, one hundred ten million, twenty thousand, one".