999356905 has 4 divisors (see below), whose sum is σ = 1199228292. Its totient is φ = 799485520.

The previous prime is 999356903. The next prime is 999356947. The reversal of 999356905 is 509653999.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 509653999 = 17 ⋅29979647.

It can be written as a sum of positive squares in 2 ways, for example, as 730134441 + 269222464 = 27021^2 + 16408^2 .

It is not a de Polignac number, because 999356905 - 2¹ = 999356903 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (999356903) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 99935686 + ... + 99935695.

It is an arithmetic number, because the mean of its divisors is an integer number (299807073).

Almost surely, 2^999356905 is an apocalyptic number.

It is an amenable number.

999356905 is a deficient number, since it is larger than the sum of its proper divisors (199871387).

999356905 is a wasteful number, since it uses less digits than its factorization.

999356905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 199871386.

The product of its (nonzero) digits is 2952450, while the sum is 55.

The square root of 999356905 is about 31612.6067416150. The cubic root of 999356905 is about 999.7855890312.

The spelling of 999356905 in words is "nine hundred ninety-nine million, three hundred fifty-six thousand, nine hundred five".