1221042313 has 2 divisors, whose sum is σ = 1221042314. Its totient is φ = 1221042312.

The previous prime is 1221042293. The next prime is 1221042337. The reversal of 1221042313 is 3132401221.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 862773129 + 358269184 = 29373^2 + 18928^2 .

It is an emirp because it is prime and its reverse (3132401221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1221042313 - 2¹³ = 1221034121 is a prime.

It is not a weakly prime, because it can be changed into another prime (1221042343) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610521156 + 610521157.

It is an arithmetic number, because the mean of its divisors is an integer number (610521157).

Almost surely, 2^1221042313 is an apocalyptic number.

It is an amenable number.

1221042313 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221042313 is an equidigital number, since it uses as much as digits as its factorization.

1221042313 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 1221042313 is about 34943.4158748111. The cubic root of 1221042313 is about 1068.8339447396.

Adding to 1221042313 its reverse (3132401221), we get a palindrome (4353443534).

The spelling of 1221042313 in words is "one billion, two hundred twenty-one million, forty-two thousand, three hundred thirteen".