1221131 has 2 divisors, whose sum is σ = 1221132.
Its totient is φ = 1221130.
The previous prime is 1221119. The next prime is 1221163. The reversal of 1221131 is 1311221.
It is a weak prime.
It is a cyclic number.
It is a de Polignac number, because none of the positive numbers 2k-1221131 is a prime.
It is a super-2 number, since 2×12211312 = 2982321838322, which contains 22 as substring.
It is a Sophie Germain prime.
It is a Chen prime.
It is not a weakly prime, because it can be changed into another prime (1221631) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610565 + 610566.
It is an arithmetic number, because the mean of its divisors is an integer number (610566).
21221131 is an apocalyptic number.
1221131 is a deficient number, since it is larger than the sum of its proper divisors (1).
1221131 is an equidigital number, since it uses as much as digits as its factorization.
1221131 is an evil number, because the sum of its binary digits is even.
The product of its digits is 12, while the sum is 11.
The square root of 1221131 is about 1105.0479627600.
The cubic root of 1221131 is about 106.8859821370.
Adding to 1221131 its reverse (1311221), we get a palindrome (2532352).
It can be divided in two parts, 1221 and 131, that multiplied together give a palindrome (159951).
The spelling of 1221131 in words is "one million, two hundred twenty-one thousand, one hundred thirty-one".