1291392499 has 2 divisors, whose sum is σ = 1291392500. Its totient is φ = 1291392498.

The previous prime is 1291392493. The next prime is 1291392503. The reversal of 1291392499 is 9942931921.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1291392499 - 2⁹ = 1291391987 is a prime.

It is not a weakly prime, because it can be changed into another prime (1291392493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 645696249 + 645696250.

It is an arithmetic number, because the mean of its divisors is an integer number (645696250).

Almost surely, 2^1291392499 is an apocalyptic number.

1291392499 is a deficient number, since it is larger than the sum of its proper divisors (1).

1291392499 is an equidigital number, since it uses as much as digits as its factorization.

1291392499 is an evil number, because the sum of its binary digits is even.

The product of its digits is 314928, while the sum is 49.

The square root of 1291392499 is about 35935.9499526588. The cubic root of 1291392499 is about 1088.9787868191.

The spelling of 1291392499 in words is "one billion, two hundred ninety-one million, three hundred ninety-two thousand, four hundred ninety-nine".