1151221 has 2 divisors, whose sum is σ = 1151222. Its totient is φ = 1151220.

The previous prime is 1151209. The next prime is 1151233. The reversal of 1151221 is 1221511.

It is a balanced prime because it is at equal distance from previous prime (1151209) and next prime (1151233).

It can be written as a sum of positive squares in only one way, i.e., 680625 + 470596 = 825^2 + 686^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1151221 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1151251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 575610 + 575611.

It is an arithmetic number, because the mean of its divisors is an integer number (575611).

2^1151221 is an apocalyptic number.

It is an amenable number.

1151221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1151221 is an equidigital number, since it uses as much as digits as its factorization.

1151221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20, while the sum is 13.

The square root of 1151221 is about 1072.9496726315. The cubic root of 1151221 is about 104.8060213020.

Adding to 1151221 its reverse (1221511), we get a palindrome (2372732).

The spelling of 1151221 in words is "one million, one hundred fifty-one thousand, two hundred twenty-one".