999981739 has 2 divisors, whose sum is σ = 999981740. Its totient is φ = 999981738.

The previous prime is 999981713. The next prime is 999981743. The reversal of 999981739 is 937189999.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 999981739 - 2²³ = 991593131 is a prime.

It is not a weakly prime, because it can be changed into another prime (999921739) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499990869 + 499990870.

It is an arithmetic number, because the mean of its divisors is an integer number (499990870).

Almost surely, 2^999981739 is an apocalyptic number.

999981739 is a deficient number, since it is larger than the sum of its proper divisors (1).

999981739 is an equidigital number, since it uses as much as digits as its factorization.

999981739 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9920232, while the sum is 64.

The square root of 999981739 is about 31622.4878686039. The cubic root of 999981739 is about 999.9939129629.

The spelling of 999981739 in words is "nine hundred ninety-nine million, nine hundred eighty-one thousand, seven hundred thirty-nine".