1221121 has 8 divisors (see below), whose sum is σ = 1375488. Its totient is φ = 1074000.

The previous prime is 1221119. The next prime is 1221131. The reversal of 1221121 is 1211221.

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 1221121 - 2¹ = 1221119 is a prime.

It is a super-2 number, since 2×1221121² = 2982272993282, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221098 and 1221107.

It is not an unprimeable number, because it can be changed into a prime (1221131) 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, 1450 + ... + 2131.

It is an arithmetic number, because the mean of its divisors is an integer number (171936).

2^1221121 is an apocalyptic number.

1221121 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1221121 is a deficient number, since it is larger than the sum of its proper divisors (154367).

1221121 is a wasteful number, since it uses less digits than its factorization.

1221121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3623.

The product of its digits is 8, while the sum is 10.

The square root of 1221121 is about 1105.0434380602. The cubic root of 1221121 is about 106.8856903685.

Adding to 1221121 its reverse (1211221), we get a palindrome (2432342).

It can be divided in two parts, 1221 and 121, that multiplied together give a palindrome (147741).

The spelling of 1221121 in words is "one million, two hundred twenty-one thousand, one hundred twenty-one".