1221120031 has 2 divisors, whose sum is σ = 1221120032. Its totient is φ = 1221120030.

The previous prime is 1221120029. The next prime is 1221120067. The reversal of 1221120031 is 1300211221.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1221120031 - 2¹ = 1221120029 is a prime.

It is a super-2 number, since 2×1221120031² = 2982268260218881922, which contains 22 as substring.

Together with 1221120029, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 1221119993 and 1221120020.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221120001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610560015 + 610560016.

It is an arithmetic number, because the mean of its divisors is an integer number (610560016).

Almost surely, 2^1221120031 is an apocalyptic number.

1221120031 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221120031 is an equidigital number, since it uses as much as digits as its factorization.

1221120031 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24, while the sum is 13.

The square root of 1221120031 is about 34944.5279121066. The cubic root of 1221120031 is about 1068.8566209601.

Adding to 1221120031 its reverse (1300211221), we get a palindrome (2521331252).

The spelling of 1221120031 in words is "one billion, two hundred twenty-one million, one hundred twenty thousand, thirty-one".