1231221029 has 2 divisors, whose sum is σ = 1231221030. Its totient is φ = 1231221028.

The previous prime is 1231221001. The next prime is 1231221037. The reversal of 1231221029 is 9201221321.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 930372004 + 300849025 = 30502^2 + 17345^2 .

It is a cyclic number.

It is not a de Polignac number, because 1231221029 - 2⁸ = 1231220773 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1231220995 and 1231221013.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1231221049) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 615610514 + 615610515.

It is an arithmetic number, because the mean of its divisors is an integer number (615610515).

Almost surely, 2^1231221029 is an apocalyptic number.

It is an amenable number.

1231221029 is a deficient number, since it is larger than the sum of its proper divisors (1).

1231221029 is an equidigital number, since it uses as much as digits as its factorization.

1231221029 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 432, while the sum is 23.

The square root of 1231221029 is about 35088.7592969600. The cubic root of 1231221029 is about 1071.7956946757.

The spelling of 1231221029 in words is "one billion, two hundred thirty-one million, two hundred twenty-one thousand, twenty-nine".