1222021021 has 4 divisors (see below), whose sum is σ = 1316022652. Its totient is φ = 1128019392.

The previous prime is 1222020953. The next prime is 1222021037. The reversal of 1222021021 is 1201202221.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 710808921 + 511212100 = 26661^2 + 22610^2 .

It is a cyclic number.

It is not a de Polignac number, because 1222021021 - 2⁷ = 1222020893 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13), and also a Moran number because the ratio is a prime number: 94001617 = 1222021021 / (1 + 2 + 2 + 2 + 0 + 2 + 1 + 0 + 2 + 1).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1222020992 and 1222021010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1222021121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 47000796 + ... + 47000821.

It is an arithmetic number, because the mean of its divisors is an integer number (329005663).

Almost surely, 2^1222021021 is an apocalyptic number.

It is an amenable number.

1222021021 is a deficient number, since it is larger than the sum of its proper divisors (94001631).

1222021021 is an equidigital number, since it uses as much as digits as its factorization.

1222021021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94001630.

The product of its (nonzero) digits is 32, while the sum is 13.

The square root of 1222021021 is about 34957.4172529951. The cubic root of 1222021021 is about 1069.1194377037.

Adding to 1222021021 its reverse (1201202221), we get a palindrome (2423223242).

The spelling of 1222021021 in words is "one billion, two hundred twenty-two million, twenty-one thousand, twenty-one".