205216718390 has 32 divisors (see below), whose sum is σ = 392094411264. Its totient is φ = 77065369600.

The previous prime is 205216718359. The next prime is 205216718431. The reversal of 205216718390 is 93817612502.

It is a super-2 number, since 2×205216718390² (a number of 23 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1437014 + ... + 1573353.

It is an arithmetic number, because the mean of its divisors is an integer number (12252950352).

Almost surely, 2^205216718390 is an apocalyptic number.

205216718390 is a deficient number, since it is larger than the sum of its proper divisors (186877692874).

205216718390 is a wasteful number, since it uses less digits than its factorization.

205216718390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3010792.

The product of its (nonzero) digits is 181440, while the sum is 44.

The spelling of 205216718390 in words is "two hundred five billion, two hundred sixteen million, seven hundred eighteen thousand, three hundred ninety".