1320123121 has 2 divisors, whose sum is σ = 1320123122. Its totient is φ = 1320123120.

The previous prime is 1320123109. The next prime is 1320123131. The reversal of 1320123121 is 1213210231.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1065369600 + 254753521 = 32640^2 + 15961^2 .

It is a cyclic number.

It is not a de Polignac number, because 1320123121 - 2²⁷ = 1185905393 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1320123095 and 1320123104.

It is not a weakly prime, because it can be changed into another prime (1320123131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 660061560 + 660061561.

It is an arithmetic number, because the mean of its divisors is an integer number (660061561).

Almost surely, 2^1320123121 is an apocalyptic number.

It is an amenable number.

1320123121 is a deficient number, since it is larger than the sum of its proper divisors (1).

1320123121 is an equidigital number, since it uses as much as digits as its factorization.

1320123121 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 16.

The square root of 1320123121 is about 36333.4986066577. The cubic root of 1320123121 is about 1096.9954152276.

Adding to 1320123121 its reverse (1213210231), we get a palindrome (2533333352).

The spelling of 1320123121 in words is "one billion, three hundred twenty million, one hundred twenty-three thousand, one hundred twenty-one".