1211011220001 has 16 divisors (see below), whose sum is σ = 1809078187968. Its totient is φ = 714109809600.

The previous prime is 1211011219949. The next prime is 1211011220051. The reversal of 1211011220001 is 1000221101121.

It is not a de Polignac number, because 1211011220001 - 2²⁶ = 1210944111137 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1211011220051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 495908370 + ... + 495910811.

It is an arithmetic number, because the mean of its divisors is an integer number (113067386748).

Almost surely, 2^{1211011220001} is an apocalyptic number.

1211011220001 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1211011220001 is a deficient number, since it is larger than the sum of its proper divisors (598066967967).

1211011220001 is a wasteful number, since it uses less digits than its factorization.

1211011220001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 991819232.

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 1211011220001 its reverse (1000221101121), we get a palindrome (2211232321122).

The spelling of 1211011220001 in words is "one trillion, two hundred eleven billion, eleven million, two hundred twenty thousand, one".