217322401 has 4 divisors (see below), whose sum is σ = 217353492. Its totient is φ = 217291312.

The previous prime is 217322393. The next prime is 217322411. The reversal of 217322401 is 104223712.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 203034001 + 14288400 = 14249^2 + 3780^2 .

It is a cyclic number.

It is not a de Polignac number, because 217322401 - 2³ = 217322393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (217322411) 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 3 ways as a sum of consecutive naturals, for example, 375 + ... + 20851.

It is an arithmetic number, because the mean of its divisors is an integer number (54338373).

Almost surely, 2^217322401 is an apocalyptic number.

It is an amenable number.

217322401 is a deficient number, since it is larger than the sum of its proper divisors (31091).

217322401 is a wasteful number, since it uses less digits than its factorization.

217322401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31090.

The product of its (nonzero) digits is 672, while the sum is 22.

The square root of 217322401 is about 14741.8588040993. The cubic root of 217322401 is about 601.2219550573.

The spelling of 217322401 in words is "two hundred seventeen million, three hundred twenty-two thousand, four hundred one".