1291192499 has 2 divisors, whose sum is σ = 1291192500. Its totient is φ = 1291192498.

The previous prime is 1291192493. The next prime is 1291192547. The reversal of 1291192499 is 9942911921.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1291192499 is a prime.

It is not a weakly prime, because it can be changed into another prime (1291192493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 645596249 + 645596250.

It is an arithmetic number, because the mean of its divisors is an integer number (645596250).

Almost surely, 2^1291192499 is an apocalyptic number.

1291192499 is a deficient number, since it is larger than the sum of its proper divisors (1).

1291192499 is an equidigital number, since it uses as much as digits as its factorization.

1291192499 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 104976, while the sum is 47.

The square root of 1291192499 is about 35933.1671161895. The cubic root of 1291192499 is about 1088.9225666273.

The spelling of 1291192499 in words is "one billion, two hundred ninety-one million, one hundred ninety-two thousand, four hundred ninety-nine".