205123021115 has 8 divisors (see below), whose sum is σ = 252151226208. Its totient is φ = 160096016320.

The previous prime is 205123021043. The next prime is 205123021121. The reversal of 205123021115 is 511120321502.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 205123021115 - 2¹² = 205123017019 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 500299847 + ... + 500300256.

It is an arithmetic number, because the mean of its divisors is an integer number (31518903276).

Almost surely, 2^205123021115 is an apocalyptic number.

205123021115 is a deficient number, since it is larger than the sum of its proper divisors (47028205093).

205123021115 is a wasteful number, since it uses less digits than its factorization.

205123021115 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1000600149.

The product of its (nonzero) digits is 600, while the sum is 23.

Adding to 205123021115 its reverse (511120321502), we get a palindrome (716243342617).

The spelling of 205123021115 in words is "two hundred five billion, one hundred twenty-three million, twenty-one thousand, one hundred fifteen".