1221012211001 has 8 divisors (see below), whose sum is σ = 1402119285600. Its totient is φ = 1051589463840.

The previous prime is 1221012210973. The next prime is 1221012211009. The reversal of 1221012211001 is 1001122101221.

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 1221012211001 - 2¹⁸ = 1221011948857 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1221012211009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2921081636 + ... + 2921082053.

It is an arithmetic number, because the mean of its divisors is an integer number (175264910700).

Almost surely, 2^{1221012211001} is an apocalyptic number.

1221012211001 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1221012211001 is a deficient number, since it is larger than the sum of its proper divisors (181107074599).

1221012211001 is a wasteful number, since it uses less digits than its factorization.

1221012211001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5842163719.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 1221012211001 its reverse (1001122101221), we get a palindrome (2222134312222).

It can be divided in two parts, 122101221 and 1001, that multiplied together give a palindrome (122223322221).

The spelling of 1221012211001 in words is "one trillion, two hundred twenty-one billion, twelve million, two hundred eleven thousand, one".