499999391 has 2 divisors, whose sum is σ = 499999392. Its totient is φ = 499999390.

The previous prime is 499999373. The next prime is 499999397. The reversal of 499999391 is 193999994.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 499999391 - 2⁶ = 499999327 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (499999397) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 249999695 + 249999696.

It is an arithmetic number, because the mean of its divisors is an integer number (249999696).

Almost surely, 2^499999391 is an apocalyptic number.

499999391 is a deficient number, since it is larger than the sum of its proper divisors (1).

499999391 is an equidigital number, since it uses as much as digits as its factorization.

499999391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6377292, while the sum is 62.

The square root of 499999391 is about 22360.6661573398. Note that the first 3 decimals coincide. The cubic root of 499999391 is about 793.7002037416.

The spelling of 499999391 in words is "four hundred ninety-nine million, nine hundred ninety-nine thousand, three hundred ninety-one".