999951109 has 2 divisors, whose sum is σ = 999951110. Its totient is φ = 999951108.

The previous prime is 999951079. The next prime is 999951131. The reversal of 999951109 is 901159999.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 999950884 + 225 = 31622^2 + 15^2 .

It is a cyclic number.

It is not a de Polignac number, because 999951109 - 2⁹ = 999950597 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (999951809) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499975554 + 499975555.

It is an arithmetic number, because the mean of its divisors is an integer number (499975555).

Almost surely, 2^999951109 is an apocalyptic number.

It is an amenable number.

999951109 is a deficient number, since it is larger than the sum of its proper divisors (1).

999951109 is an equidigital number, since it uses as much as digits as its factorization.

999951109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 295245, while the sum is 52.

The square root of 999951109 is about 31622.0035576495. The cubic root of 999951109 is about 999.9837027344.

The spelling of 999951109 in words is "nine hundred ninety-nine million, nine hundred fifty-one thousand, one hundred nine".