218135943 has 16 divisors (see below), whose sum is σ = 324864000. Its totient is φ = 144659160.

The previous prime is 218135917. The next prime is 218135971. The reversal of 218135943 is 349531812.

It is not a de Polignac number, because 218135943 - 2¹² = 218131847 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 218135898 and 218135907.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218135543) 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 15 ways as a sum of consecutive naturals, for example, 15993 + ... + 26306.

It is an arithmetic number, because the mean of its divisors is an integer number (20304000).

Almost surely, 2^218135943 is an apocalyptic number.

218135943 is a deficient number, since it is larger than the sum of its proper divisors (106728057).

218135943 is a wasteful number, since it uses less digits than its factorization.

218135943 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42499 (or 42493 counting only the distinct ones).

The product of its digits is 25920, while the sum is 36.

The square root of 218135943 is about 14769.4259536381. The cubic root of 218135943 is about 601.9712415852.

It can be divided in two parts, 218 and 135943, that added together give a square (136161 = 369²).

The spelling of 218135943 in words is "two hundred eighteen million, one hundred thirty-five thousand, nine hundred forty-three".