217638235844623 has 16 divisors (see below), whose sum is σ = 238798427193216. Its totient is φ = 196707218041440.

The previous prime is 217638235844591. The next prime is 217638235844629. The reversal of 217638235844623 is 326448532836712.

It is a cyclic number.

It is not a de Polignac number, because 217638235844623 - 2⁵ = 217638235844591 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217638235844629) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 197978536 + ... + 199074802.

It is an arithmetic number, because the mean of its divisors is an integer number (14924901699576).

Almost surely, 2^{217638235844623} is an apocalyptic number.

217638235844623 is a deficient number, since it is larger than the sum of its proper divisors (21160191348593).

217638235844623 is a wasteful number, since it uses less digits than its factorization.

217638235844623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1200774.

The product of its digits is 278691840, while the sum is 64.

The spelling of 217638235844623 in words is "two hundred seventeen trillion, six hundred thirty-eight billion, two hundred thirty-five million, eight hundred forty-four thousand, six hundred twenty-three".