1121421221 has 4 divisors (see below), whose sum is σ = 1126113600. Its totient is φ = 1116728844.

The previous prime is 1121421181. The next prime is 1121421251. The reversal of 1121421221 is 1221241211.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1121421221 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1121421221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1121421251) 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, 2345831 + ... + 2346308.

It is an arithmetic number, because the mean of its divisors is an integer number (281528400).

Almost surely, 2^1121421221 is an apocalyptic number.

It is an amenable number.

1121421221 is a deficient number, since it is larger than the sum of its proper divisors (4692379).

1121421221 is an equidigital number, since it uses as much as digits as its factorization.

1121421221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4692378.

The product of its digits is 64, while the sum is 17.

The square root of 1121421221 is about 33487.6278795617. The cubic root of 1121421221 is about 1038.9379014644.

Adding to 1121421221 its reverse (1221241211), we get a palindrome (2342662432).

The spelling of 1121421221 in words is "one billion, one hundred twenty-one million, four hundred twenty-one thousand, two hundred twenty-one".