1011001221221 has 4 divisors (see below), whose sum is σ = 1028136835200. Its totient is φ = 993865607244.

The previous prime is 1011001221193. The next prime is 1011001221283. The reversal of 1011001221221 is 1221221001101.

1011001221221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1011001221221 - 2¹⁸ = 1011000959077 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1011001221196 and 1011001221205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1011001221121) 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, 8567806901 + ... + 8567807018.

It is an arithmetic number, because the mean of its divisors is an integer number (257034208800).

Almost surely, 2^{1011001221221} is an apocalyptic number.

It is an amenable number.

1011001221221 is a deficient number, since it is larger than the sum of its proper divisors (17135613979).

1011001221221 is an equidigital number, since it uses as much as digits as its factorization.

1011001221221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17135613978.

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

Adding to 1011001221221 its reverse (1221221001101), we get a palindrome (2232222222322).

The spelling of 1011001221221 in words is "one trillion, eleven billion, one million, two hundred twenty-one thousand, two hundred twenty-one".