208128945123 has 32 divisors (see below), whose sum is σ = 338249260800. Its totient is φ = 125434036800.

The previous prime is 208128945119. The next prime is 208128945169. The reversal of 208128945123 is 321549821802.

208128945123 is a `hidden beast` number, since 2 + 0 + 8 + 128 + 9 + 4 + 512 + 3 = 666.

It is not a de Polignac number, because 208128945123 - 2² = 208128945119 is a prime.

It is not an unprimeable number, because it can be changed into a prime (208128945173) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1904298 + ... + 2010623.

It is an arithmetic number, because the mean of its divisors is an integer number (10570289400).

Almost surely, 2^208128945123 is an apocalyptic number.

208128945123 is a deficient number, since it is larger than the sum of its proper divisors (130120315677).

208128945123 is a wasteful number, since it uses less digits than its factorization.

208128945123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3915120 (or 3915114 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 45.

The spelling of 208128945123 in words is "two hundred eight billion, one hundred twenty-eight million, nine hundred forty-five thousand, one hundred twenty-three".