9911223121 has 2 divisors, whose sum is σ = 9911223122. Its totient is φ = 9911223120.

The previous prime is 9911223103. The next prime is 9911223139. The reversal of 9911223121 is 1213221199.

It is a balanced prime because it is at equal distance from previous prime (9911223103) and next prime (9911223139).

It can be written as a sum of positive squares in only one way, i.e., 5497481025 + 4413742096 = 74145^2 + 66436^2 .

It is a cyclic number.

It is not a de Polignac number, because 9911223121 - 2¹⁵ = 9911190353 is a prime.

It is not a weakly prime, because it can be changed into another prime (9911229121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4955611560 + 4955611561.

It is an arithmetic number, because the mean of its divisors is an integer number (4955611561).

Almost surely, 2^9911223121 is an apocalyptic number.

It is an amenable number.

9911223121 is a deficient number, since it is larger than the sum of its proper divisors (1).

9911223121 is an equidigital number, since it uses as much as digits as its factorization.

9911223121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1944, while the sum is 31.

The square root of 9911223121 is about 99555.1260408021. The cubic root of 9911223121 is about 2148.0402637010.

The spelling of 9911223121 in words is "nine billion, nine hundred eleven million, two hundred twenty-three thousand, one hundred twenty-one".