1291169969 has 2 divisors, whose sum is σ = 1291169970. Its totient is φ = 1291169968.

The previous prime is 1291169959. The next prime is 1291169989. The reversal of 1291169969 is 9699611921.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1285939600 + 5230369 = 35860^2 + 2287^2 .

It is an emirp because it is prime and its reverse (9699611921) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1291169969 - 2⁴ = 1291169953 is a prime.

It is a super-2 number, since 2×1291169969² = 3334239777694921922, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1291169969.

It is not a weakly prime, because it can be changed into another prime (1291169939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 645584984 + 645584985.

It is an arithmetic number, because the mean of its divisors is an integer number (645584985).

Almost surely, 2^1291169969 is an apocalyptic number.

It is an amenable number.

1291169969 is a deficient number, since it is larger than the sum of its proper divisors (1).

1291169969 is an equidigital number, since it uses as much as digits as its factorization.

1291169969 is an evil number, because the sum of its binary digits is even.

The product of its digits is 472392, while the sum is 53.

The square root of 1291169969 is about 35932.8536161547. The cubic root of 1291169969 is about 1088.9162330589.

The spelling of 1291169969 in words is "one billion, two hundred ninety-one million, one hundred sixty-nine thousand, nine hundred sixty-nine".