1011021221221 has 4 divisors (see below), whose sum is σ = 1102932241344. Its totient is φ = 919110201100.

The previous prime is 1011021221179. The next prime is 1011021221251. The reversal of 1011021221221 is 1221221201101.

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 1011021221221 - 2¹⁵ = 1011021188453 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1011021221195 and 1011021221204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1011021221251) 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 3 ways as a sum of consecutive naturals, for example, 45955510045 + ... + 45955510066.

It is an arithmetic number, because the mean of its divisors is an integer number (275733060336).

Almost surely, 2^{1011021221221} is an apocalyptic number.

1011021221221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1011021221221 is a deficient number, since it is larger than the sum of its proper divisors (91911020123).

1011021221221 is an equidigital number, since it uses as much as digits as its factorization.

1011021221221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91911020122.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 1011021221221 its reverse (1221221201101), we get a palindrome (2232242422322).

The spelling of 1011021221221 in words is "one trillion, eleven billion, twenty-one million, two hundred twenty-one thousand, two hundred twenty-one".