217385390738 has 16 divisors (see below), whose sum is σ = 332333222976. Its totient is φ = 106608918000.

The previous prime is 217385390683. The next prime is 217385390773. The reversal of 217385390738 is 837093583712.

217385390738 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29195 + ... + 660017.

It is an arithmetic number, because the mean of its divisors is an integer number (20770826436).

Almost surely, 2^217385390738 is an apocalyptic number.

217385390738 is a deficient number, since it is larger than the sum of its proper divisors (114947832238).

217385390738 is a wasteful number, since it uses less digits than its factorization.

217385390738 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 634129.

The product of its (nonzero) digits is 7620480, while the sum is 56.

The spelling of 217385390738 in words is "two hundred seventeen billion, three hundred eighty-five million, three hundred ninety thousand, seven hundred thirty-eight".