1011222221 has 4 divisors (see below), whose sum is σ = 1011934272. Its totient is φ = 1010510172.

The previous prime is 1011222217. The next prime is 1011222239. The reversal of 1011222221 is 1222221101.

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, and also an emirpimes, since its reverse is a distinct semiprime: 1222221101 = 1543 ⋅792107.

It is a cyclic number.

It is not a de Polignac number, because 1011222221 - 2² = 1011222217 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1011222196 and 1011222205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1011222211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 353891 + ... + 356736.

It is an arithmetic number, because the mean of its divisors is an integer number (252983568).

Almost surely, 2^1011222221 is an apocalyptic number.

It is an amenable number.

1011222221 is a deficient number, since it is larger than the sum of its proper divisors (712051).

1011222221 is an equidigital number, since it uses as much as digits as its factorization.

1011222221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 712050.

The product of its (nonzero) digits is 32, while the sum is 14.

The square root of 1011222221 is about 31799.7204547461. The cubic root of 1011222221 is about 1003.7268337889.

Adding to 1011222221 its reverse (1222221101), we get a palindrome (2233443322).

It can be divided in two parts, 101 and 1222221, that multiplied together give a palindrome (123444321).

The spelling of 1011222221 in words is "one billion, eleven million, two hundred twenty-two thousand, two hundred twenty-one".