228221313781 has 4 divisors (see below), whose sum is σ = 228222319500. Its totient is φ = 228220308064.

The previous prime is 228221313773. The next prime is 228221313809. The reversal of 228221313781 is 187313122822.

228221313781 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 108927061681 + 119294252100 = 330041^2 + 345390^2 .

It is a cyclic number.

It is not a de Polignac number, because 228221313781 - 2³ = 228221313773 is a prime.

It is a super-2 number, since 2×228221313781² (a number of 24 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 (228221313701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15945 + ... + 675793.

It is an arithmetic number, because the mean of its divisors is an integer number (57055579875).

Almost surely, 2^228221313781 is an apocalyptic number.

It is an amenable number.

228221313781 is a deficient number, since it is larger than the sum of its proper divisors (1005719).

228221313781 is an equidigital number, since it uses as much as digits as its factorization.

228221313781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1005718.

The product of its digits is 64512, while the sum is 40.

The spelling of 228221313781 in words is "two hundred twenty-eight billion, two hundred twenty-one million, three hundred thirteen thousand, seven hundred eighty-one".