217121733 has 12 divisors (see below), whose sum is σ = 315264768. Its totient is φ = 143988840.

The previous prime is 217121693. The next prime is 217121789. The reversal of 217121733 is 337121712.

It is not a de Polignac number, because 217121733 - 2⁶ = 217121669 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 217121697 and 217121706.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217121533) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 61435 + ... + 64872.

It is an arithmetic number, because the mean of its divisors is an integer number (26272064).

Almost surely, 2^217121733 is an apocalyptic number.

It is an amenable number.

217121733 is a deficient number, since it is larger than the sum of its proper divisors (98143035).

217121733 is a wasteful number, since it uses less digits than its factorization.

217121733 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126504 (or 126501 counting only the distinct ones).

The product of its digits is 1764, while the sum is 27.

The square root of 217121733 is about 14735.0511705932. The cubic root of 217121733 is about 601.0368488752.

The spelling of 217121733 in words is "two hundred seventeen million, one hundred twenty-one thousand, seven hundred thirty-three".