299985991 has 2 divisors, whose sum is σ = 299985992. Its totient is φ = 299985990.

The previous prime is 299985967. The next prime is 299985997. The reversal of 299985991 is 199589992.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 299985991 - 2¹⁹ = 299461703 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (299985997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 149992995 + 149992996.

It is an arithmetic number, because the mean of its divisors is an integer number (149992996).

Almost surely, 2^299985991 is an apocalyptic number.

299985991 is a deficient number, since it is larger than the sum of its proper divisors (1).

299985991 is an equidigital number, since it uses as much as digits as its factorization.

299985991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4723920, while the sum is 61.

The square root of 299985991 is about 17320.1036659715. The cubic root of 299985991 is about 669.4225298242.

The spelling of 299985991 in words is "two hundred ninety-nine million, nine hundred eighty-five thousand, nine hundred ninety-one".