218137923 has 6 divisors (see below), whose sum is σ = 315088124. Its totient is φ = 145425276.

The previous prime is 218137883. The next prime is 218137939. The reversal of 218137923 is 329731812.

It is not a de Polignac number, because 218137923 - 2⁹ = 218137411 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (218137123) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 12118765 + ... + 12118782.

Almost surely, 2^218137923 is an apocalyptic number.

218137923 is a deficient number, since it is larger than the sum of its proper divisors (96950201).

218137923 is a wasteful number, since it uses less digits than its factorization.

218137923 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24237553 (or 24237550 counting only the distinct ones).

The product of its digits is 18144, while the sum is 36.

The square root of 218137923 is about 14769.4929838502. The cubic root of 218137923 is about 601.9730629257.

It can be divided in two parts, 2181 and 37923, that added together give a palindrome (40104).

The spelling of 218137923 in words is "two hundred eighteen million, one hundred thirty-seven thousand, nine hundred twenty-three".