1262128139 has 2 divisors, whose sum is σ = 1262128140. Its totient is φ = 1262128138.

The previous prime is 1262128123. The next prime is 1262128157. The reversal of 1262128139 is 9318212621.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1262128139 - 2⁴ = 1262128123 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1262128099 and 1262128108.

It is not a weakly prime, because it can be changed into another prime (1262128199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 631064069 + 631064070.

It is an arithmetic number, because the mean of its divisors is an integer number (631064070).

Almost surely, 2^1262128139 is an apocalyptic number.

1262128139 is a deficient number, since it is larger than the sum of its proper divisors (1).

1262128139 is an equidigital number, since it uses as much as digits as its factorization.

1262128139 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10368, while the sum is 35.

The square root of 1262128139 is about 35526.4428137690. The cubic root of 1262128139 is about 1080.6900422721.

The spelling of 1262128139 in words is "one billion, two hundred sixty-two million, one hundred twenty-eight thousand, one hundred thirty-nine".