1011211221221 has 8 divisors (see below), whose sum is σ = 1072135289664. Its totient is φ = 950447270080.

The previous prime is 1011211221217. The next prime is 1011211221277. The reversal of 1011211221221 is 1221221121101.

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 1011211221221 - 2² = 1011211221217 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1011211221221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1011211221281) 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, 40016315 + ... + 40041576.

It is an arithmetic number, because the mean of its divisors is an integer number (134016911208).

Almost surely, 2^{1011211221221} is an apocalyptic number.

It is an amenable number.

1011211221221 is a deficient number, since it is larger than the sum of its proper divisors (60924068443).

1011211221221 is an equidigital number, since it uses as much as digits as its factorization.

1011211221221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80058651.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 1011211221221 its reverse (1221221121101), we get a palindrome (2232432342322).

The spelling of 1011211221221 in words is "one trillion, eleven billion, two hundred eleven million, two hundred twenty-one thousand, two hundred twenty-one".