1271201521 has 2 divisors, whose sum is σ = 1271201522. Its totient is φ = 1271201520.

The previous prime is 1271201471. The next prime is 1271201549. The reversal of 1271201521 is 1251021721.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1234538496 + 36663025 = 35136^2 + 6055^2 .

It is a cyclic number.

It is not a de Polignac number, because 1271201521 - 2¹¹ = 1271199473 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1271201492 and 1271201501.

It is not a weakly prime, because it can be changed into another prime (1271205521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 635600760 + 635600761.

It is an arithmetic number, because the mean of its divisors is an integer number (635600761).

Almost surely, 2^1271201521 is an apocalyptic number.

It is an amenable number.

1271201521 is a deficient number, since it is larger than the sum of its proper divisors (1).

1271201521 is an equidigital number, since it uses as much as digits as its factorization.

1271201521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 280, while the sum is 22.

The square root of 1271201521 is about 35653.9131232464. The cubic root of 1271201521 is about 1083.2735384959.

The spelling of 1271201521 in words is "one billion, two hundred seventy-one million, two hundred one thousand, five hundred twenty-one".