1221111097 has 2 divisors, whose sum is σ = 1221111098. Its totient is φ = 1221111096.

The previous prime is 1221111083. The next prime is 1221111167. The reversal of 1221111097 is 7901111221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1206242361 + 14868736 = 34731^2 + 3856^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1221111097 is a prime.

It is a super-2 number, since 2×1221111097² = 2982224622433086818, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1221111007) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610555548 + 610555549.

It is an arithmetic number, because the mean of its divisors is an integer number (610555549).

Almost surely, 2^1221111097 is an apocalyptic number.

It is an amenable number.

1221111097 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221111097 is an equidigital number, since it uses as much as digits as its factorization.

1221111097 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 252, while the sum is 25.

The square root of 1221111097 is about 34944.4000806996. The cubic root of 1221111097 is about 1068.8540142853.

The spelling of 1221111097 in words is "one billion, two hundred twenty-one million, one hundred eleven thousand, ninety-seven".