1221302981 has 2 divisors, whose sum is σ = 1221302982. Its totient is φ = 1221302980.

The previous prime is 1221302977. The next prime is 1221303049. The reversal of 1221302981 is 1892031221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 672572356 + 548730625 = 25934^2 + 23425^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221302981 - 2² = 1221302977 is a prime.

It is a super-2 number, since 2×1221302981² = 2983161942798972722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221302911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610651490 + 610651491.

It is an arithmetic number, because the mean of its divisors is an integer number (610651491).

Almost surely, 2^1221302981 is an apocalyptic number.

It is an amenable number.

1221302981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221302981 is an equidigital number, since it uses as much as digits as its factorization.

1221302981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 29.

The square root of 1221302981 is about 34947.1455343637. The cubic root of 1221302981 is about 1068.9099975185.

The spelling of 1221302981 in words is "one billion, two hundred twenty-one million, three hundred two thousand, nine hundred eighty-one".