221031231020 has 12 divisors (see below), whose sum is σ = 464165585184. Its totient is φ = 88412492400.

The previous prime is 221031231013. The next prime is 221031231049. The reversal of 221031231020 is 20132130122.

It is a super-2 number, since 2×221031231020² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 221031231020.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5525780756 + ... + 5525780795.

It is an arithmetic number, because the mean of its divisors is an integer number (38680465432).

Almost surely, 2^221031231020 is an apocalyptic number.

221031231020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221031231020 is an abundant number, since it is smaller than the sum of its proper divisors (243134354164).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221031231020 is a wasteful number, since it uses less digits than its factorization.

221031231020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11051561560 (or 11051561558 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 221031231020 its reverse (20132130122), we get a palindrome (241163361142).

The spelling of 221031231020 in words is "two hundred twenty-one billion, thirty-one million, two hundred thirty-one thousand, twenty".