1261369129 has 2 divisors, whose sum is σ = 1261369130. Its totient is φ = 1261369128.

The previous prime is 1261369099. The next prime is 1261369139. The reversal of 1261369129 is 9219631621.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1120709529 + 140659600 = 33477^2 + 11860^2 .

It is a cyclic number.

It is not a de Polignac number, because 1261369129 - 2⁵ = 1261369097 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1261369091 and 1261369100.

It is not a weakly prime, because it can be changed into another prime (1261369139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 630684564 + 630684565.

It is an arithmetic number, because the mean of its divisors is an integer number (630684565).

Almost surely, 2^1261369129 is an apocalyptic number.

It is an amenable number.

1261369129 is a deficient number, since it is larger than the sum of its proper divisors (1).

1261369129 is an equidigital number, since it uses as much as digits as its factorization.

1261369129 is an evil number, because the sum of its binary digits is even.

The product of its digits is 34992, while the sum is 40.

The square root of 1261369129 is about 35515.7588825017. The cubic root of 1261369129 is about 1080.4733661663.

The spelling of 1261369129 in words is "one billion, two hundred sixty-one million, three hundred sixty-nine thousand, one hundred twenty-nine".