1221247 has 2 divisors, whose sum is σ = 1221248. Its totient is φ = 1221246.

The previous prime is 1221239. The next prime is 1221251. The reversal of 1221247 is 7421221.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1221247 - 2³ = 1221239 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1228247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610623 + 610624.

It is an arithmetic number, because the mean of its divisors is an integer number (610624).

2^1221247 is an apocalyptic number.

1221247 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221247 is an equidigital number, since it uses as much as digits as its factorization.

1221247 is an evil number, because the sum of its binary digits is even.

The product of its digits is 224, while the sum is 19.

The square root of 1221247 is about 1105.1004479232. The cubic root of 1221247 is about 106.8893665354.

Adding to 1221247 its reverse (7421221), we get a palindrome (8642468).

It can be divided in two parts, 122 and 1247, that added together give a square (1369 = 37²).

The spelling of 1221247 in words is "one million, two hundred twenty-one thousand, two hundred forty-seven".