1271999903 has 2 divisors, whose sum is σ = 1271999904. Its totient is φ = 1271999902.

The previous prime is 1271999873. The next prime is 1271999917. The reversal of 1271999903 is 3099991721.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1271999903 - 2¹² = 1271995807 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1271999203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 635999951 + 635999952.

It is an arithmetic number, because the mean of its divisors is an integer number (635999952).

Almost surely, 2^1271999903 is an apocalyptic number.

1271999903 is a deficient number, since it is larger than the sum of its proper divisors (1).

1271999903 is an equidigital number, since it uses as much as digits as its factorization.

1271999903 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 275562, while the sum is 50.

The square root of 1271999903 is about 35665.1076403815. The cubic root of 1271999903 is about 1083.5002754536.

The spelling of 1271999903 in words is "one billion, two hundred seventy-one million, nine hundred ninety-nine thousand, nine hundred three".