1222220021 has 8 divisors (see below), whose sum is σ = 1333584000. Its totient is φ = 1110898240.

The previous prime is 1222220009. The next prime is 1222220029. The reversal of 1222220021 is 1200222221.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1222220021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1222219978 and 1222220005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1222220029) 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, 107780 + ... + 118578.

It is an arithmetic number, because the mean of its divisors is an integer number (166698000).

Almost surely, 2^1222220021 is an apocalyptic number.

1222220021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1222220021 is a deficient number, since it is larger than the sum of its proper divisors (111363979).

1222220021 is a wasteful number, since it uses less digits than its factorization.

1222220021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21099.

The product of its (nonzero) digits is 64, while the sum is 14.

The square root of 1222220021 is about 34960.2634572453. The cubic root of 1222220021 is about 1069.1774681350.

Adding to 1222220021 its reverse (1200222221), we get a palindrome (2422442242).

It can be divided in two parts, 12222200 and 21, that added together give a palindrome (12222221).

The spelling of 1222220021 in words is "one billion, two hundred twenty-two million, two hundred twenty thousand, twenty-one".