1271998091 has 16 divisors (see below), whose sum is σ = 1577877504. Its totient is φ = 998482464.

The previous prime is 1271998081. The next prime is 1271998103. The reversal of 1271998091 is 1908991721.

It is not a de Polignac number, because 1271998091 - 2¹⁴ = 1271981707 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1271998031) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 43475 + ... + 66588.

It is an arithmetic number, because the mean of its divisors is an integer number (98617344).

Almost surely, 2^1271998091 is an apocalyptic number.

1271998091 is a deficient number, since it is larger than the sum of its proper divisors (305879413).

1271998091 is a wasteful number, since it uses less digits than its factorization.

1271998091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110210.

The product of its (nonzero) digits is 81648, while the sum is 47.

The square root of 1271998091 is about 35665.0822373929. The cubic root of 1271998091 is about 1083.4997609611.

The spelling of 1271998091 in words is "one billion, two hundred seventy-one million, nine hundred ninety-eight thousand, ninety-one".