218738874021 has 16 divisors (see below), whose sum is σ = 304380979584. Its totient is φ = 139463368704.

The previous prime is 218738874017. The next prime is 218738874031. The reversal of 218738874021 is 120478837812.

It is not a de Polignac number, because 218738874021 - 2² = 218738874017 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218738874001) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 187125 + ... + 687381.

It is an arithmetic number, because the mean of its divisors is an integer number (19023811224).

Almost surely, 2^218738874021 is an apocalyptic number.

It is an amenable number.

218738874021 is a deficient number, since it is larger than the sum of its proper divisors (85642105563).

218738874021 is a wasteful number, since it uses less digits than its factorization.

218738874021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 506620.

The product of its (nonzero) digits is 1204224, while the sum is 51.

The spelling of 218738874021 in words is "two hundred eighteen billion, seven hundred thirty-eight million, eight hundred seventy-four thousand, twenty-one".