217323438 has 16 divisors (see below), whose sum is σ = 435642240. Its totient is φ = 72275256.

The previous prime is 217323413. The next prime is 217323439. The reversal of 217323438 is 834323712.

It is a junction number, because it is equal to n+sod(n) for n = 217323399 and 217323408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217323439) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 38620 + ... + 43887.

It is an arithmetic number, because the mean of its divisors is an integer number (27227640).

Almost surely, 2^217323438 is an apocalyptic number.

217323438 is an abundant number, since it is smaller than the sum of its proper divisors (218318802).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

217323438 is a wasteful number, since it uses less digits than its factorization.

217323438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82951.

The product of its digits is 24192, while the sum is 33.

The square root of 217323438 is about 14741.8939760127. The cubic root of 217323438 is about 601.2229113419. Note that the first 3 decimals are identical.

The spelling of 217323438 in words is "two hundred seventeen million, three hundred twenty-three thousand, four hundred thirty-eight".