1221000029 has 2 divisors, whose sum is σ = 1221000030. Its totient is φ = 1221000028.

The previous prime is 1221000017. The next prime is 1221000031. The reversal of 1221000029 is 9200001221.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 719687929 + 501312100 = 26827^2 + 22390^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1221000029 is a prime.

Together with 1221000031, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 1220999980 and 1221000016.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1221000089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610500014 + 610500015.

It is an arithmetic number, because the mean of its divisors is an integer number (610500015).

Almost surely, 2^1221000029 is an apocalyptic number.

It is an amenable number.

1221000029 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221000029 is an equidigital number, since it uses as much as digits as its factorization.

1221000029 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72, while the sum is 17.

The square root of 1221000029 is about 34942.8108342761. The cubic root of 1221000029 is about 1068.8216068935.

The spelling of 1221000029 in words is "one billion, two hundred twenty-one million, twenty-nine", and thus it is an aban number.