1220111021 has 8 divisors (see below), whose sum is σ = 1225645344. Its totient is φ = 1214587440.

The previous prime is 1220111017. The next prime is 1220111033. The reversal of 1220111021 is 1201110221.

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 1220111021 - 2² = 1220111017 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1220110993 and 1220111011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220117021) 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, 296051 + ... + 300143.

It is an arithmetic number, because the mean of its divisors is an integer number (153205668).

Almost surely, 2^1220111021 is an apocalyptic number.

It is an amenable number.

1220111021 is a deficient number, since it is larger than the sum of its proper divisors (5534323).

1220111021 is an equidigital number, since it uses as much as digits as its factorization.

1220111021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5371.

The product of its (nonzero) digits is 8, while the sum is 11.

The square root of 1220111021 is about 34930.0876179834. The cubic root of 1220111021 is about 1068.5621415262.

Adding to 1220111021 its reverse (1201110221), we get a palindrome (2421221242).

It can be divided in two parts, 1 and 220111021, that added together give a palindrome (220111022).

The spelling of 1220111021 in words is "one billion, two hundred twenty million, one hundred eleven thousand, twenty-one".