218203822021 has 4 divisors (see below), whose sum is σ = 221460595552. Its totient is φ = 214947048492.

The previous prime is 218203822019. The next prime is 218203822049. The reversal of 218203822021 is 120228302812.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 218203822021 - 2¹ = 218203822019 is a prime.

It is a super-2 number, since 2×218203822021² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218203829021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1628386665 + ... + 1628386798.

It is an arithmetic number, because the mean of its divisors is an integer number (55365148888).

Almost surely, 2^218203822021 is an apocalyptic number.

It is an amenable number.

218203822021 is a deficient number, since it is larger than the sum of its proper divisors (3256773531).

218203822021 is an equidigital number, since it uses as much as digits as its factorization.

218203822021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3256773530.

The product of its (nonzero) digits is 6144, while the sum is 31.

The spelling of 218203822021 in words is "two hundred eighteen billion, two hundred three million, eight hundred twenty-two thousand, twenty-one".