1221001100201 has 8 divisors (see below), whose sum is σ = 1224339247560. Its totient is φ = 1217663975808.

The previous prime is 1221001100197. The next prime is 1221001100213. The reversal of 1221001100201 is 1020011001221.

It can be written as a sum of positive squares in 4 ways, for example, as 58218451225 + 1162782648976 = 241285^2 + 1078324^2 .

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 1221001100201 - 2² = 1221001100197 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221001100251) 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, 2165975 + ... + 2670851.

It is an arithmetic number, because the mean of its divisors is an integer number (153042405945).

Almost surely, 2^{1221001100201} is an apocalyptic number.

It is an amenable number.

1221001100201 is a deficient number, since it is larger than the sum of its proper divisors (3338147359).

1221001100201 is an equidigital number, since it uses as much as digits as its factorization.

1221001100201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 511483.

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

Adding to 1221001100201 its reverse (1020011001221), we get a palindrome (2241012101422).

The spelling of 1221001100201 in words is "one trillion, two hundred twenty-one billion, one million, one hundred thousand, two hundred one".