1221101 has 4 divisors (see below), whose sum is σ = 1395552. Its totient is φ = 1046652.

The previous prime is 1221097. The next prime is 1221113. The reversal of 1221101 is 1011221.

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 not a de Polignac number, because 1221101 - 2² = 1221097 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 87215 + ... + 87228.

It is an arithmetic number, because the mean of its divisors is an integer number (348888).

2^1221101 is an apocalyptic number.

It is an amenable number.

1221101 is a deficient number, since it is larger than the sum of its proper divisors (174451).

1221101 is an equidigital number, since it uses as much as digits as its factorization.

1221101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 174450.

The product of its (nonzero) digits is 4, while the sum is 8.

The square root of 1221101 is about 1105.0343886052. The cubic root of 1221101 is about 106.8851068267.

Adding to 1221101 its reverse (1011221), we get a palindrome (2232322).

It can be divided in two parts, 1221 and 101, that multiplied together give a palindrome (123321).

The spelling of 1221101 in words is "one million, two hundred twenty-one thousand, one hundred one".